diff --git a/bazarr/api/episodes/history.py b/bazarr/api/episodes/history.py
index ca3e8a500..026397363 100644
--- a/bazarr/api/episodes/history.py
+++ b/bazarr/api/episodes/history.py
@@ -150,7 +150,7 @@ def get(self):
             del item['external_subtitles']
 
             if item['score']:
-                item['score'] = str(round((int(item['score']) * 100 / 360), 2)) + "%"
+                item['score'] = f"{round((int(item['score']) * 100 / 360), 2)}%"
 
             # Make timestamp pretty
             if item['timestamp']:
diff --git a/bazarr/api/movies/history.py b/bazarr/api/movies/history.py
index d7587607c..d7e7d6783 100644
--- a/bazarr/api/movies/history.py
+++ b/bazarr/api/movies/history.py
@@ -141,7 +141,7 @@ def get(self):
             del item['external_subtitles']
 
             if item['score']:
-                item['score'] = str(round((int(item['score']) * 100 / 120), 2)) + "%"
+                item['score'] = f"{round((int(item['score']) * 100 / 120), 2)}%"
 
             # Make timestamp pretty
             if item['timestamp']:
diff --git a/bazarr/api/system/releases.py b/bazarr/api/system/releases.py
index e4848c597..12922dace 100644
--- a/bazarr/api/system/releases.py
+++ b/bazarr/api/system/releases.py
@@ -58,5 +58,6 @@ def get(self):
 
         except Exception:
             logging.exception(
-                'BAZARR cannot parse releases caching file: ' + os.path.join(args.config_dir, 'config', 'releases.txt'))
+                f'BAZARR cannot parse releases caching file: '
+                f'{os.path.join(args.config_dir, "config", "releases.txt")}')
         return marshal(filtered_releases, self.get_response_model, envelope='data')
diff --git a/bazarr/api/webhooks/plex.py b/bazarr/api/webhooks/plex.py
index 3eede2584..e04743001 100644
--- a/bazarr/api/webhooks/plex.py
+++ b/bazarr/api/webhooks/plex.py
@@ -62,7 +62,7 @@ def post(self):
         if media_type == 'episode':
             try:
                 episode_imdb_id = [x['imdb'] for x in ids if 'imdb' in x][0]
-                r = requests.get('https://imdb.com/title/{}'.format(episode_imdb_id),
+                r = requests.get(f'https://imdb.com/title/{episode_imdb_id}',
                                  headers={"User-Agent": os.environ["SZ_USER_AGENT"]})
                 soup = bso(r.content, "html.parser")
                 script_tag = soup.find(id='__NEXT_DATA__')
diff --git a/bazarr/app/app.py b/bazarr/app/app.py
index 53a6270de..c5a5bf89d 100644
--- a/bazarr/app/app.py
+++ b/bazarr/app/app.py
@@ -34,7 +34,7 @@ def create_app():
     else:
         app.config["DEBUG"] = False
 
-    socketio.init_app(app, path=base_url.rstrip('/')+'/api/socket.io', cors_allowed_origins='*',
+    socketio.init_app(app, path=f'{base_url.rstrip("/")}/api/socket.io', cors_allowed_origins='*',
                       async_mode='threading', allow_upgrades=False, transports='polling')
 
     @app.errorhandler(404)
diff --git a/bazarr/app/check_update.py b/bazarr/app/check_update.py
index a8ced6ace..327294324 100644
--- a/bazarr/app/check_update.py
+++ b/bazarr/app/check_update.py
@@ -24,7 +24,7 @@ def check_releases():
     releases = []
     url_releases = 'https://api.github.com/repos/morpheus65535/Bazarr/releases?per_page=100'
     try:
-        logging.debug('BAZARR getting releases from Github: {}'.format(url_releases))
+        logging.debug(f'BAZARR getting releases from Github: {url_releases}')
         r = requests.get(url_releases, allow_redirects=True)
         r.raise_for_status()
     except requests.exceptions.HTTPError:
@@ -50,7 +50,7 @@ def check_releases():
                              'download_link': download_link})
         with open(os.path.join(args.config_dir, 'config', 'releases.txt'), 'w') as f:
             json.dump(releases, f)
-        logging.debug('BAZARR saved {} releases to releases.txt'.format(len(r.json())))
+        logging.debug(f'BAZARR saved {len(r.json())} releases to releases.txt')
 
 
 def check_if_new_update():
@@ -59,9 +59,9 @@ def check_if_new_update():
     elif settings.general.branch == 'development':
         use_prerelease = True
     else:
-        logging.error('BAZARR unknown branch provided to updater: {}'.format(settings.general.branch))
+        logging.error(f'BAZARR unknown branch provided to updater: {settings.general.branch}')
         return
-    logging.debug('BAZARR updater is using {} branch'.format(settings.general.branch))
+    logging.debug(f'BAZARR updater is using {settings.general.branch} branch')
 
     check_releases()
 
@@ -84,7 +84,7 @@ def check_if_new_update():
                 release = next((item for item in data if not item["prerelease"]), None)
 
         if release and 'name' in release:
-            logging.debug('BAZARR last release available is {}'.format(release['name']))
+            logging.debug(f'BAZARR last release available is {release["name"]}')
             if deprecated_python_version():
                 logging.warning('BAZARR is using a deprecated Python version, you must update Python to get latest '
                                 'version available.')
@@ -101,12 +101,12 @@ def check_if_new_update():
 
             # skip update process if latest release is v0.9.1.1 which is the latest pre-semver compatible release
             if new_version and release['name'] != 'v0.9.1.1':
-                logging.debug('BAZARR newer release available and will be downloaded: {}'.format(release['name']))
+                logging.debug(f'BAZARR newer release available and will be downloaded: {release["name"]}')
                 download_release(url=release['download_link'])
             # rolling back from nightly to stable release
             elif current_version:
                 if current_version.prerelease and not use_prerelease:
-                    logging.debug('BAZARR previous stable version will be downloaded: {}'.format(release['name']))
+                    logging.debug(f'BAZARR previous stable version will be downloaded: {release["name"]}')
                     download_release(url=release['download_link'])
             else:
                 logging.debug('BAZARR no newer release have been found')
@@ -122,9 +122,9 @@ def download_release(url):
     try:
         os.makedirs(update_dir, exist_ok=True)
     except Exception:
-        logging.debug('BAZARR unable to create update directory {}'.format(update_dir))
+        logging.debug(f'BAZARR unable to create update directory {update_dir}')
     else:
-        logging.debug('BAZARR downloading release from Github: {}'.format(url))
+        logging.debug(f'BAZARR downloading release from Github: {url}')
         r = requests.get(url, allow_redirects=True)
     if r:
         try:
@@ -145,7 +145,7 @@ def apply_update():
 
     if os.path.isdir(update_dir):
         if os.path.isfile(bazarr_zip):
-            logging.debug('BAZARR is trying to unzip this release to {0}: {1}'.format(bazarr_dir, bazarr_zip))
+            logging.debug(f'BAZARR is trying to unzip this release to {bazarr_dir}: {bazarr_zip}')
             try:
                 with ZipFile(bazarr_zip, 'r') as archive:
                     zip_root_directory = ''
@@ -195,7 +195,7 @@ def apply_update():
 def update_cleaner(zipfile, bazarr_dir, config_dir):
     with ZipFile(zipfile, 'r') as archive:
         file_in_zip = archive.namelist()
-    logging.debug('BAZARR zip file contain {} directories and files'.format(len(file_in_zip)))
+    logging.debug(f'BAZARR zip file contain {len(file_in_zip)} directories and files')
     separator = os.path.sep
     if os.path.sep == '\\':
         logging.debug('BAZARR upgrade leftover cleaner is running on Windows. We\'ll fix the zip file separator '
@@ -207,33 +207,33 @@ def update_cleaner(zipfile, bazarr_dir, config_dir):
         logging.debug('BAZARR upgrade leftover cleaner is running on something else than Windows. The zip file '
                       'separator are fine.')
 
-    dir_to_ignore = ['^.' + separator,
-                     '^bin' + separator,
-                     '^venv' + separator,
-                     '^WinPython' + separator,
-                     separator + '__pycache__' + separator + '$']
+    dir_to_ignore = [f'^.{separator}',
+                     f'^bin{separator}',
+                     f'^venv{separator}',
+                     f'^WinPython{separator}',
+                     f'{separator}__pycache__{separator}$']
     if os.path.abspath(bazarr_dir).lower() == os.path.abspath(config_dir).lower():
         # for users who installed Bazarr inside the config directory (ie: `%programdata%\Bazarr` on windows)
-        dir_to_ignore.append('^backup' + separator)
-        dir_to_ignore.append('^cache' + separator)
-        dir_to_ignore.append('^config' + separator)
-        dir_to_ignore.append('^db' + separator)
-        dir_to_ignore.append('^log' + separator)
-        dir_to_ignore.append('^restore' + separator)
-        dir_to_ignore.append('^update' + separator)
+        dir_to_ignore.append(f'^backup{separator}')
+        dir_to_ignore.append(f'^cache{separator}')
+        dir_to_ignore.append(f'^config{separator}')
+        dir_to_ignore.append(f'^db{separator}')
+        dir_to_ignore.append(f'^log{separator}')
+        dir_to_ignore.append(f'^restore{separator}')
+        dir_to_ignore.append(f'^update{separator}')
     elif os.path.abspath(bazarr_dir).lower() in os.path.abspath(config_dir).lower():
         # when config directory is a child of Bazarr installation directory
-        dir_to_ignore.append('^' + os.path.relpath(config_dir, bazarr_dir) + separator)
+        dir_to_ignore.append(f'^{os.path.relpath(config_dir, bazarr_dir)}{separator}')
     dir_to_ignore_regex_string = '(?:% s)' % '|'.join(dir_to_ignore)
     logging.debug(f'BAZARR upgrade leftover cleaner will ignore directories matching this '
                   f'regex: {dir_to_ignore_regex_string}')
     dir_to_ignore_regex = re.compile(dir_to_ignore_regex_string)
 
     file_to_ignore = ['nssm.exe', '7za.exe', 'unins000.exe', 'unins000.dat']
-    logging.debug('BAZARR upgrade leftover cleaner will ignore those files: {}'.format(', '.join(file_to_ignore)))
+    logging.debug(f'BAZARR upgrade leftover cleaner will ignore those files: {", ".join(file_to_ignore)}')
     extension_to_ignore = ['.pyc']
-    logging.debug('BAZARR upgrade leftover cleaner will ignore files with those extensions: '
-                  '{}'.format(', '.join(extension_to_ignore)))
+    logging.debug(
+        f'BAZARR upgrade leftover cleaner will ignore files with those extensions: {", ".join(extension_to_ignore)}')
 
     file_on_disk = []
     folder_list = []
@@ -256,14 +256,14 @@ def update_cleaner(zipfile, bazarr_dir, config_dir):
                 filepath = os.path.join(current_dir, file)
                 if not dir_to_ignore_regex.findall(filepath):
                     file_on_disk.append(filepath)
-    logging.debug('BAZARR directory contain {} files'.format(len(file_on_disk)))
-    logging.debug('BAZARR directory contain {} directories'.format(len(folder_list)))
+    logging.debug(f'BAZARR directory contain {len(file_on_disk)} files')
+    logging.debug(f'BAZARR directory contain {len(folder_list)} directories')
     file_on_disk += folder_list
-    logging.debug('BAZARR directory contain {} directories and files'.format(len(file_on_disk)))
+    logging.debug(f'BAZARR directory contain {len(file_on_disk)} directories and files')
 
     file_to_remove = list(set(file_on_disk) - set(file_in_zip))
-    logging.debug('BAZARR will delete {} directories and files'.format(len(file_to_remove)))
-    logging.debug('BAZARR will delete this: {}'.format(', '.join(file_to_remove)))
+    logging.debug(f'BAZARR will delete {len(file_to_remove)} directories and files')
+    logging.debug(f'BAZARR will delete this: {", ".join(file_to_remove)}')
 
     for file in file_to_remove:
         filepath = os.path.join(bazarr_dir, file)
@@ -273,4 +273,4 @@ def update_cleaner(zipfile, bazarr_dir, config_dir):
             else:
                 os.remove(filepath)
         except Exception:
-            logging.debug('BAZARR upgrade leftover cleaner cannot delete {}'.format(filepath))
+            logging.debug(f'BAZARR upgrade leftover cleaner cannot delete {filepath}')
diff --git a/bazarr/app/config.py b/bazarr/app/config.py
index 7fd566433..bf128c6f8 100644
--- a/bazarr/app/config.py
+++ b/bazarr/app/config.py
@@ -346,7 +346,7 @@ def convert_ini_to_yaml(config_file):
                 output_dict[section].update({item[0]: item[1]})
     with open(os.path.join(os.path.dirname(config_file), 'config.yaml'), 'w') as file:
         yaml.dump(output_dict, file)
-    os.rename(config_file, config_file + '.old')
+    os.rename(config_file, f'{config_file}.old')
 
 
 config_yaml_file = os.path.join(args.config_dir, 'config', 'config.yaml')
@@ -761,10 +761,10 @@ def configure_captcha_func():
 def configure_proxy_func():
     if settings.proxy.type:
         if settings.proxy.username != '' and settings.proxy.password != '':
-            proxy = settings.proxy.type + '://' + quote_plus(settings.proxy.username) + ':' + \
-                    quote_plus(settings.proxy.password) + '@' + settings.proxy.url + ':' + str(settings.proxy.port)
+            proxy = (f'{settings.proxy.type}://{quote_plus(settings.proxy.username)}:'
+                     f'{quote_plus(settings.proxy.password)}@{settings.proxy.url}:{settings.proxy.port}')
         else:
-            proxy = settings.proxy.type + '://' + settings.proxy.url + ':' + str(settings.proxy.port)
+            proxy = f'{settings.proxy.type}://{settings.proxy.url}:{settings.proxy.port}'
         os.environ['HTTP_PROXY'] = str(proxy)
         os.environ['HTTPS_PROXY'] = str(proxy)
         exclude = ','.join(settings.proxy.exclude)
diff --git a/bazarr/app/database.py b/bazarr/app/database.py
index 880cc1f8b..690bda40b 100644
--- a/bazarr/app/database.py
+++ b/bazarr/app/database.py
@@ -330,11 +330,11 @@ def get_exclusion_clause(exclusion_type):
     if exclusion_type == 'series':
         tagsList = settings.sonarr.excluded_tags
         for tag in tagsList:
-            where_clause.append(~(TableShows.tags.contains("\'" + tag + "\'")))
+            where_clause.append(~(TableShows.tags.contains(f"\'{tag}\'")))
     else:
         tagsList = settings.radarr.excluded_tags
         for tag in tagsList:
-            where_clause.append(~(TableMovies.tags.contains("\'" + tag + "\'")))
+            where_clause.append(~(TableMovies.tags.contains(f"\'{tag}\'")))
 
     if exclusion_type == 'series':
         monitoredOnly = settings.sonarr.only_monitored
diff --git a/bazarr/app/logger.py b/bazarr/app/logger.py
index 91e3b0fe7..abf832aa9 100644
--- a/bazarr/app/logger.py
+++ b/bazarr/app/logger.py
@@ -160,7 +160,7 @@ def getFilesToDelete(self):
         result = []
         # See bpo-44753: Don't use the extension when computing the prefix.
         n, e = os.path.splitext(baseName)
-        prefix = n + '.'
+        prefix = f'{n}.'
         plen = len(prefix)
         for fileName in fileNames:
             if self.namer is None:
diff --git a/bazarr/app/notifier.py b/bazarr/app/notifier.py
index 6d97fb13b..931a700a4 100644
--- a/bazarr/app/notifier.py
+++ b/bazarr/app/notifier.py
@@ -24,7 +24,7 @@ def update_notifier():
     for x in results['schemas']:
         if x['service_name'] not in notifiers_in_db:
             notifiers_added.append({'name': str(x['service_name']), 'enabled': 0})
-            logging.debug('Adding new notifier agent: ' + str(x['service_name']))
+            logging.debug(f'Adding new notifier agent: {x["service_name"]}')
         else:
             notifiers_kept.append(x['service_name'])
 
@@ -60,7 +60,7 @@ def send_notifications(sonarr_series_id, sonarr_episode_id, message):
     series_title = series.title
     series_year = series.year
     if series_year not in [None, '', '0']:
-        series_year = ' ({})'.format(series_year)
+        series_year = f' ({series_year})'
     else:
         series_year = ''
     episode = database.execute(
@@ -80,8 +80,7 @@ def send_notifications(sonarr_series_id, sonarr_episode_id, message):
 
     apobj.notify(
         title='Bazarr notification',
-        body="{}{} - S{:02d}E{:02d} - {} : {}".format(series_title, series_year, episode.season, episode.episode,
-                                                      episode.title, message),
+        body=f"{series_title}{series_year} - S{episode.season:02d}E{episode.episode:02d} - {episode.title} : {message}",
     )
 
 
@@ -98,7 +97,7 @@ def send_notifications_movie(radarr_id, message):
     movie_title = movie.title
     movie_year = movie.year
     if movie_year not in [None, '', '0']:
-        movie_year = ' ({})'.format(movie_year)
+        movie_year = f' ({movie_year})'
     else:
         movie_year = ''
 
@@ -112,5 +111,5 @@ def send_notifications_movie(radarr_id, message):
 
     apobj.notify(
         title='Bazarr notification',
-        body="{}{} : {}".format(movie_title, movie_year, message),
+        body=f"{movie_title}{movie_year} : {message}",
     )
diff --git a/bazarr/app/scheduler.py b/bazarr/app/scheduler.py
index 054ad6f3d..8abdab14e 100644
--- a/bazarr/app/scheduler.py
+++ b/bazarr/app/scheduler.py
@@ -127,10 +127,10 @@ def get_time_from_cron(cron):
             if day == "*":
                 text = "everyday"
             else:
-                text = "every " + day_name[int(day)]
+                text = f"every {day_name[int(day)]}"
 
             if hour != "*":
-                text += " at " + hour + ":00"
+                text += f" at {hour}:00"
 
             return text
 
@@ -149,7 +149,7 @@ def get_time_from_cron(cron):
                 running = False
 
             if isinstance(job.trigger, IntervalTrigger):
-                interval = "every " + get_time_from_interval(job.trigger.__getstate__()['interval'])
+                interval = f"every {get_time_from_interval(job.trigger.__getstate__()['interval'])}"
                 task_list.append({'name': job.name, 'interval': interval, 'next_run_in': next_run,
                                   'next_run_time': next_run, 'job_id': job.id, 'job_running': running})
             elif isinstance(job.trigger, CronTrigger):
diff --git a/bazarr/app/server.py b/bazarr/app/server.py
index c9d14bd31..48db3912a 100644
--- a/bazarr/app/server.py
+++ b/bazarr/app/server.py
@@ -77,13 +77,13 @@ def shutdown(self):
         try:
             self.server.close()
         except Exception as e:
-            logging.error('BAZARR Cannot stop Waitress: ' + repr(e))
+            logging.error(f'BAZARR Cannot stop Waitress: {repr(e)}')
         else:
             database.close()
             try:
                 stop_file = io.open(os.path.join(args.config_dir, "bazarr.stop"), "w", encoding='UTF-8')
             except Exception as e:
-                logging.error('BAZARR Cannot create stop file: ' + repr(e))
+                logging.error(f'BAZARR Cannot create stop file: {repr(e)}')
             else:
                 logging.info('Bazarr is being shutdown...')
                 stop_file.write(str(''))
@@ -94,13 +94,13 @@ def restart(self):
         try:
             self.server.close()
         except Exception as e:
-            logging.error('BAZARR Cannot stop Waitress: ' + repr(e))
+            logging.error(f'BAZARR Cannot stop Waitress: {repr(e)}')
         else:
             database.close()
             try:
                 restart_file = io.open(os.path.join(args.config_dir, "bazarr.restart"), "w", encoding='UTF-8')
             except Exception as e:
-                logging.error('BAZARR Cannot create restart file: ' + repr(e))
+                logging.error(f'BAZARR Cannot create restart file: {repr(e)}')
             else:
                 logging.info('Bazarr is being restarted...')
                 restart_file.write(str(''))
diff --git a/bazarr/app/signalr_client.py b/bazarr/app/signalr_client.py
index 5e78a12ea..2f048eb17 100644
--- a/bazarr/app/signalr_client.py
+++ b/bazarr/app/signalr_client.py
@@ -45,8 +45,9 @@ def __init__(self):
 
     def start(self):
         if get_sonarr_info.is_legacy():
-            logging.warning('BAZARR can only sync from Sonarr v3 SignalR feed to get real-time update. You should '
-                            'consider upgrading your version({}).'.format(get_sonarr_info.version()))
+            logging.warning(
+                f'BAZARR can only sync from Sonarr v3 SignalR feed to get real-time update. You should consider '
+                f'upgrading your version({get_sonarr_info.version()}).')
         else:
             self.connected = False
             event_stream(type='badges')
@@ -98,7 +99,7 @@ def exception_handler(self):
 
     def configure(self):
         self.apikey_sonarr = settings.sonarr.apikey
-        self.connection = Connection(url_sonarr() + "/signalr", self.session)
+        self.connection = Connection(f"{url_sonarr()}/signalr", self.session)
         self.connection.qs = {'apikey': self.apikey_sonarr}
         sonarr_hub = self.connection.register_hub('')  # Sonarr doesn't use named hub
 
@@ -158,7 +159,7 @@ def on_reconnect_handler(self):
     def configure(self):
         self.apikey_sonarr = settings.sonarr.apikey
         self.connection = HubConnectionBuilder() \
-            .with_url(url_sonarr() + "/signalr/messages?access_token={}".format(self.apikey_sonarr),
+            .with_url(f"{url_sonarr()}/signalr/messages?access_token={self.apikey_sonarr}",
                       options={
                           "verify_ssl": False,
                           "headers": headers
@@ -225,7 +226,7 @@ def on_reconnect_handler(self):
     def configure(self):
         self.apikey_radarr = settings.radarr.apikey
         self.connection = HubConnectionBuilder() \
-            .with_url(url_radarr() + "/signalr/messages?access_token={}".format(self.apikey_radarr),
+            .with_url(f"{url_radarr()}/signalr/messages?access_token={self.apikey_radarr}",
                       options={
                           "verify_ssl": False,
                           "headers": headers
@@ -306,7 +307,7 @@ def dispatcher(data):
             update_one_movie(movie_id=media_id, action=action,
                              defer_search=settings.radarr.defer_search_signalr)
     except Exception as e:
-        logging.debug('BAZARR an exception occurred while parsing SignalR feed: {}'.format(repr(e)))
+        logging.debug(f'BAZARR an exception occurred while parsing SignalR feed: {repr(e)}')
     finally:
         event_stream(type='badges')
         return
diff --git a/bazarr/app/ui.py b/bazarr/app/ui.py
index 21c4894a7..821d2ed21 100644
--- a/bazarr/app/ui.py
+++ b/bazarr/app/ui.py
@@ -110,11 +110,9 @@ def series_images(url):
     apikey = settings.sonarr.apikey
     baseUrl = settings.sonarr.base_url
     if get_sonarr_info.is_legacy():
-        url_image = (url_sonarr() + '/api/' + url.lstrip(baseUrl) + '?apikey=' +
-                     apikey).replace('poster-250', 'poster-500')
+        url_image = f'{url_sonarr()}/api/{url.lstrip(baseUrl)}?apikey={apikey}'.replace('poster-250', 'poster-500')
     else:
-        url_image = (url_sonarr() + '/api/v3/' + url.lstrip(baseUrl) + '?apikey=' +
-                     apikey).replace('poster-250', 'poster-500')
+        url_image = f'{url_sonarr()}/api/v3/{url.lstrip(baseUrl)}?apikey={apikey}'.replace('poster-250', 'poster-500')
     try:
         req = requests.get(url_image, stream=True, timeout=15, verify=False, headers=headers)
     except Exception:
@@ -129,9 +127,9 @@ def movies_images(url):
     apikey = settings.radarr.apikey
     baseUrl = settings.radarr.base_url
     if get_radarr_info.is_legacy():
-        url_image = url_radarr() + '/api/' + url.lstrip(baseUrl) + '?apikey=' + apikey
+        url_image = f'{url_radarr()}/api/{url.lstrip(baseUrl)}?apikey={apikey}'
     else:
-        url_image = url_radarr() + '/api/v3/' + url.lstrip(baseUrl) + '?apikey=' + apikey
+        url_image = f'{url_radarr()}/api/v3/{url.lstrip(baseUrl)}?apikey={apikey}'
     try:
         req = requests.get(url_image, stream=True, timeout=15, verify=False, headers=headers)
     except Exception:
@@ -171,7 +169,7 @@ def configured():
 def proxy(protocol, url):
     if protocol.lower() not in ['http', 'https']:
         return dict(status=False, error='Unsupported protocol')
-    url = protocol + '://' + unquote(url)
+    url = f'{protocol}://{unquote(url)}'
     params = request.args
     try:
         result = requests.get(url, params, allow_redirects=False, verify=False, timeout=5, headers=headers)
diff --git a/bazarr/init.py b/bazarr/init.py
index 2afbba48d..03264bf72 100644
--- a/bazarr/init.py
+++ b/bazarr/init.py
@@ -28,7 +28,7 @@
 restore_from_backup()
 
 # set subliminal_patch user agent
-os.environ["SZ_USER_AGENT"] = "Bazarr/{}".format(os.environ["BAZARR_VERSION"])
+os.environ["SZ_USER_AGENT"] = f"Bazarr/{os.environ['BAZARR_VERSION']}"
 
 # Check if args.config_dir exist
 if not os.path.exists(args.config_dir):
@@ -96,7 +96,7 @@ def is_virtualenv():
                         pip_command.insert(4, '--user')
                     subprocess.check_output(pip_command, stderr=subprocess.STDOUT)
                 except subprocess.CalledProcessError as e:
-                    logging.exception('BAZARR requirements.txt installation result: {}'.format(e.stdout))
+                    logging.exception(f'BAZARR requirements.txt installation result: {e.stdout}')
                     os._exit(1)
                 else:
                     logging.info('BAZARR requirements installed.')
@@ -104,7 +104,7 @@ def is_virtualenv():
                 try:
                     restart_file = io.open(os.path.join(args.config_dir, "bazarr.restart"), "w", encoding='UTF-8')
                 except Exception as e:
-                    logging.error('BAZARR Cannot create restart file: ' + repr(e))
+                    logging.error(f'BAZARR Cannot create restart file: {repr(e)}')
                 else:
                     logging.info('Bazarr is being restarted...')
                     restart_file.write(str(''))
diff --git a/bazarr/main.py b/bazarr/main.py
index e6186848e..970684d14 100644
--- a/bazarr/main.py
+++ b/bazarr/main.py
@@ -47,7 +47,7 @@
     try:
         stop_file = io.open(os.path.join(args.config_dir, "bazarr.stop"), "w", encoding='UTF-8')
     except Exception as e:
-        logging.error('BAZARR Cannot create stop file: ' + repr(e))
+        logging.error(f'BAZARR Cannot create stop file: {repr(e)}')
     else:
         create_db_revision(app)
         logging.info('Bazarr is being shutdown...')
diff --git a/bazarr/radarr/filesystem.py b/bazarr/radarr/filesystem.py
index d8cb0e2e9..ea6284999 100644
--- a/bazarr/radarr/filesystem.py
+++ b/bazarr/radarr/filesystem.py
@@ -13,15 +13,16 @@ def browse_radarr_filesystem(path='#'):
         path = ''
 
     if get_radarr_info.is_legacy():
-        url_radarr_api_filesystem = url_radarr() + "/api/filesystem?path=" + path + \
-                                    "&allowFoldersWithoutTrailingSlashes=true&includeFiles=false&apikey=" + \
-                                    settings.radarr.apikey
+        url_radarr_api_filesystem = (f"{url_radarr()}/api/filesystem?path={path}&"
+                                     f"allowFoldersWithoutTrailingSlashes=true&includeFiles=false&"
+                                     f"apikey={settings.radarr.apikey}")
     else:
-        url_radarr_api_filesystem = url_radarr() + "/api/v3/filesystem?path=" + path + \
-                                    "&allowFoldersWithoutTrailingSlashes=true&includeFiles=false&apikey=" + \
-                                    settings.radarr.apikey
+        url_radarr_api_filesystem = (f"{url_radarr()}/api/v3/filesystem?path={path}&"
+                                     f"allowFoldersWithoutTrailingSlashes=true&includeFiles=false&"
+                                     f"apikey={settings.radarr.apikey}")
     try:
-        r = requests.get(url_radarr_api_filesystem, timeout=int(settings.radarr.http_timeout), verify=False, headers=headers)
+        r = requests.get(url_radarr_api_filesystem, timeout=int(settings.radarr.http_timeout), verify=False,
+                         headers=headers)
         r.raise_for_status()
     except requests.exceptions.HTTPError:
         logging.exception("BAZARR Error trying to get series from Radarr. Http error.")
diff --git a/bazarr/radarr/info.py b/bazarr/radarr/info.py
index cdac0ee65..c60980e51 100644
--- a/bazarr/radarr/info.py
+++ b/bazarr/radarr/info.py
@@ -28,23 +28,25 @@ def version():
             radarr_version = ''
         if settings.general.use_radarr:
             try:
-                rv = url_radarr() + "/api/system/status?apikey=" + settings.radarr.apikey
-                radarr_json = requests.get(rv, timeout=int(settings.radarr.http_timeout), verify=False, headers=headers).json()
+                rv = f"{url_radarr()}/api/system/status?apikey={settings.radarr.apikey}"
+                radarr_json = requests.get(rv, timeout=int(settings.radarr.http_timeout), verify=False,
+                                           headers=headers).json()
                 if 'version' in radarr_json:
                     radarr_version = radarr_json['version']
                 else:
                     raise json.decoder.JSONDecodeError
             except json.decoder.JSONDecodeError:
                 try:
-                    rv = url_radarr() + "/api/v3/system/status?apikey=" + settings.radarr.apikey
-                    radarr_version = requests.get(rv, timeout=int(settings.radarr.http_timeout), verify=False, headers=headers).json()['version']
+                    rv = f"{url_radarr()}/api/v3/system/status?apikey={settings.radarr.apikey}"
+                    radarr_version = requests.get(rv, timeout=int(settings.radarr.http_timeout), verify=False,
+                                                  headers=headers).json()['version']
                 except json.decoder.JSONDecodeError:
                     logging.debug('BAZARR cannot get Radarr version')
                     radarr_version = 'unknown'
             except Exception:
                 logging.debug('BAZARR cannot get Radarr version')
                 radarr_version = 'unknown'
-        logging.debug('BAZARR got this Radarr version from its API: {}'.format(radarr_version))
+        logging.debug(f'BAZARR got this Radarr version from its API: {radarr_version}')
         region.set("radarr_version", radarr_version)
         return radarr_version
 
@@ -83,7 +85,7 @@ def url_radarr():
     if settings.radarr.base_url == '':
         settings.radarr.base_url = "/"
     if not settings.radarr.base_url.startswith("/"):
-        settings.radarr.base_url = "/" + settings.radarr.base_url
+        settings.radarr.base_url = f"/{settings.radarr.base_url}"
     if settings.radarr.base_url.endswith("/"):
         settings.radarr.base_url = settings.radarr.base_url[:-1]
 
diff --git a/bazarr/radarr/notify.py b/bazarr/radarr/notify.py
index d2204b2b3..ae0a7f51f 100644
--- a/bazarr/radarr/notify.py
+++ b/bazarr/radarr/notify.py
@@ -11,9 +11,9 @@
 def notify_radarr(radarr_id):
     try:
         if get_radarr_info.is_legacy():
-            url = url_radarr() + "/api/command?apikey=" + settings.radarr.apikey
+            url = f"{url_radarr()}/api/command?apikey={settings.radarr.apikey}"
         else:
-            url = url_radarr() + "/api/v3/command?apikey=" + settings.radarr.apikey
+            url = f"{url_radarr()}/api/v3/command?apikey={settings.radarr.apikey}"
         data = {
             'name': 'RescanMovie',
             'movieId': int(radarr_id)
diff --git a/bazarr/radarr/rootfolder.py b/bazarr/radarr/rootfolder.py
index 2bfadb9bc..f2d8b9ef6 100644
--- a/bazarr/radarr/rootfolder.py
+++ b/bazarr/radarr/rootfolder.py
@@ -17,9 +17,9 @@ def get_radarr_rootfolder():
 
     # Get root folder data from Radarr
     if get_radarr_info.is_legacy():
-        url_radarr_api_rootfolder = url_radarr() + "/api/rootfolder?apikey=" + apikey_radarr
+        url_radarr_api_rootfolder = f"{url_radarr()}/api/rootfolder?apikey={apikey_radarr}"
     else:
-        url_radarr_api_rootfolder = url_radarr() + "/api/v3/rootfolder?apikey=" + apikey_radarr
+        url_radarr_api_rootfolder = f"{url_radarr()}/api/v3/rootfolder?apikey={apikey_radarr}"
 
     try:
         rootfolder = requests.get(url_radarr_api_rootfolder, timeout=int(settings.radarr.http_timeout), verify=False, headers=headers)
diff --git a/bazarr/radarr/sync/movies.py b/bazarr/radarr/sync/movies.py
index 34e137139..17929ffb0 100644
--- a/bazarr/radarr/sync/movies.py
+++ b/bazarr/radarr/sync/movies.py
@@ -155,7 +155,7 @@ def update_movies(send_event=True):
 
 
 def update_one_movie(movie_id, action, defer_search=False):
-    logging.debug('BAZARR syncing this specific movie from Radarr: {}'.format(movie_id))
+    logging.debug(f'BAZARR syncing this specific movie from Radarr: {movie_id}')
 
     # Check if there's a row in database for this movie ID
     existing_movie = database.execute(
@@ -175,8 +175,9 @@ def update_one_movie(movie_id, action, defer_search=False):
                               f"because of {e}")
             else:
                 event_stream(type='movie', action='delete', payload=int(movie_id))
-                logging.debug('BAZARR deleted this movie from the database:{}'.format(path_mappings.path_replace_movie(
-                    existing_movie.path)))
+                logging.debug(
+                    f'BAZARR deleted this movie from the database: '
+                    f'{path_mappings.path_replace_movie(existing_movie.path)}')
         return
 
     movie_default_enabled = settings.general.movie_default_enabled
@@ -224,8 +225,8 @@ def update_one_movie(movie_id, action, defer_search=False):
                           f"of {e}")
         else:
             event_stream(type='movie', action='delete', payload=int(movie_id))
-            logging.debug('BAZARR deleted this movie from the database:{}'.format(path_mappings.path_replace_movie(
-                existing_movie.path)))
+            logging.debug(
+                f'BAZARR deleted this movie from the database:{path_mappings.path_replace_movie(existing_movie.path)}')
         return
 
     # Update existing movie in DB
@@ -240,8 +241,8 @@ def update_one_movie(movie_id, action, defer_search=False):
                           f"of {e}")
         else:
             event_stream(type='movie', action='update', payload=int(movie_id))
-            logging.debug('BAZARR updated this movie into the database:{}'.format(path_mappings.path_replace_movie(
-                movie['path'])))
+            logging.debug(
+                f'BAZARR updated this movie into the database:{path_mappings.path_replace_movie(movie["path"])}')
 
     # Insert new movie in DB
     elif movie and not existing_movie:
@@ -254,19 +255,19 @@ def update_one_movie(movie_id, action, defer_search=False):
                           f"of {e}")
         else:
             event_stream(type='movie', action='update', payload=int(movie_id))
-            logging.debug('BAZARR inserted this movie into the database:{}'.format(path_mappings.path_replace_movie(
-                movie['path'])))
+            logging.debug(
+                f'BAZARR inserted this movie into the database:{path_mappings.path_replace_movie(movie["path"])}')
 
     # Storing existing subtitles
-    logging.debug('BAZARR storing subtitles for this movie: {}'.format(path_mappings.path_replace_movie(
-            movie['path'])))
+    logging.debug(f'BAZARR storing subtitles for this movie: {path_mappings.path_replace_movie(movie["path"])}')
     store_subtitles_movie(movie['path'], path_mappings.path_replace_movie(movie['path']))
 
     # Downloading missing subtitles
     if defer_search:
-        logging.debug('BAZARR searching for missing subtitles is deferred until scheduled task execution for this '
-                      'movie: {}'.format(path_mappings.path_replace_movie(movie['path'])))
+        logging.debug(
+            f'BAZARR searching for missing subtitles is deferred until scheduled task execution for this movie: '
+            f'{path_mappings.path_replace_movie(movie["path"])}')
     else:
-        logging.debug('BAZARR downloading missing subtitles for this movie: {}'.format(path_mappings.path_replace_movie(
-            movie['path'])))
+        logging.debug(
+            f'BAZARR downloading missing subtitles for this movie: {path_mappings.path_replace_movie(movie["path"])}')
         movies_download_subtitles(movie_id)
diff --git a/bazarr/radarr/sync/parser.py b/bazarr/radarr/sync/parser.py
index b70b5e682..0d7e915ee 100644
--- a/bazarr/radarr/sync/parser.py
+++ b/bazarr/radarr/sync/parser.py
@@ -25,7 +25,7 @@ def movieParser(movie, action, tags_dict, movie_default_profile, audio_profiles)
             overview = ""
         try:
             poster_big = movie['images'][0]['url']
-            poster = os.path.splitext(poster_big)[0] + '-500' + os.path.splitext(poster_big)[1]
+            poster = f'{os.path.splitext(poster_big)[0]}-500{os.path.splitext(poster_big)[1]}'
         except Exception:
             poster = ""
         try:
@@ -56,7 +56,7 @@ def movieParser(movie, action, tags_dict, movie_default_profile, audio_profiles)
         except Exception:
             format = movie['movieFile']['quality']['quality']['name']
             try:
-                resolution = str(movie['movieFile']['quality']['quality']['resolution']) + 'p'
+                resolution = f'{movie["movieFile"]["quality"]["quality"]["resolution"]}p'
             except Exception:
                 resolution = None
 
diff --git a/bazarr/radarr/sync/utils.py b/bazarr/radarr/sync/utils.py
index b36bee50b..6096786f4 100644
--- a/bazarr/radarr/sync/utils.py
+++ b/bazarr/radarr/sync/utils.py
@@ -13,9 +13,9 @@ def get_profile_list():
     profiles_list = []
     # Get profiles data from radarr
     if get_radarr_info.is_legacy():
-        url_radarr_api_movies = url_radarr() + "/api/profile?apikey=" + apikey_radarr
+        url_radarr_api_movies = f"{url_radarr()}/api/profile?apikey={apikey_radarr}"
     else:
-        url_radarr_api_movies = url_radarr() + "/api/v3/qualityprofile?apikey=" + apikey_radarr
+        url_radarr_api_movies = f"{url_radarr()}/api/v3/qualityprofile?apikey={apikey_radarr}"
 
     try:
         profiles_json = requests.get(url_radarr_api_movies, timeout=int(settings.radarr.http_timeout), verify=False, headers=headers)
@@ -45,9 +45,9 @@ def get_tags():
 
     # Get tags data from Radarr
     if get_radarr_info.is_legacy():
-        url_radarr_api_series = url_radarr() + "/api/tag?apikey=" + apikey_radarr
+        url_radarr_api_series = f"{url_radarr()}/api/tag?apikey={apikey_radarr}"
     else:
-        url_radarr_api_series = url_radarr() + "/api/v3/tag?apikey=" + apikey_radarr
+        url_radarr_api_series = f"{url_radarr()}/api/v3/tag?apikey={apikey_radarr}"
 
     try:
         tagsDict = requests.get(url_radarr_api_series, timeout=int(settings.radarr.http_timeout), verify=False, headers=headers)
@@ -72,11 +72,9 @@ def get_tags():
 
 def get_movies_from_radarr_api(url, apikey_radarr, radarr_id=None):
     if get_radarr_info.is_legacy():
-        url_radarr_api_movies = url + "/api/movie" + ("/{}".format(radarr_id) if radarr_id else "") + "?apikey=" + \
-                                apikey_radarr
+        url_radarr_api_movies = f'{url}/api/movie{f"/{radarr_id}" if radarr_id else ""}?apikey={apikey_radarr}'
     else:
-        url_radarr_api_movies = url + "/api/v3/movie" + ("/{}".format(radarr_id) if radarr_id else "") + "?apikey=" + \
-                                apikey_radarr
+        url_radarr_api_movies = f'{url}/api/v3/movie{f"/{radarr_id}" if radarr_id else ""}?apikey={apikey_radarr}'
 
     try:
         r = requests.get(url_radarr_api_movies, timeout=int(settings.radarr.http_timeout), verify=False, headers=headers)
diff --git a/bazarr/sonarr/filesystem.py b/bazarr/sonarr/filesystem.py
index 25bb66f08..a0f48d278 100644
--- a/bazarr/sonarr/filesystem.py
+++ b/bazarr/sonarr/filesystem.py
@@ -12,15 +12,16 @@ def browse_sonarr_filesystem(path='#'):
     if path == '#':
         path = ''
     if get_sonarr_info.is_legacy():
-        url_sonarr_api_filesystem = url_sonarr() + "/api/filesystem?path=" + path + \
-                                    "&allowFoldersWithoutTrailingSlashes=true&includeFiles=false&apikey=" + \
-                                    settings.sonarr.apikey
+        url_sonarr_api_filesystem = (f"{url_sonarr()}/api/filesystem?path={path}&"
+                                     f"allowFoldersWithoutTrailingSlashes=true&includeFiles=false&"
+                                     f"apikey={settings.sonarr.apikey}")
     else:
-        url_sonarr_api_filesystem = url_sonarr() + "/api/v3/filesystem?path=" + path + \
-                                    "&allowFoldersWithoutTrailingSlashes=true&includeFiles=false&apikey=" + \
-                                    settings.sonarr.apikey
+        url_sonarr_api_filesystem = (f"{url_sonarr()}/api/v3/filesystem?path={path}&"
+                                     f"allowFoldersWithoutTrailingSlashes=true&includeFiles=false&"
+                                     f"apikey={settings.sonarr.apikey}")
     try:
-        r = requests.get(url_sonarr_api_filesystem, timeout=int(settings.sonarr.http_timeout), verify=False, headers=headers)
+        r = requests.get(url_sonarr_api_filesystem, timeout=int(settings.sonarr.http_timeout), verify=False,
+                         headers=headers)
         r.raise_for_status()
     except requests.exceptions.HTTPError:
         logging.exception("BAZARR Error trying to get series from Sonarr. Http error.")
diff --git a/bazarr/sonarr/info.py b/bazarr/sonarr/info.py
index 706ea6de7..e36aa54e7 100644
--- a/bazarr/sonarr/info.py
+++ b/bazarr/sonarr/info.py
@@ -28,23 +28,25 @@ def version():
             sonarr_version = ''
         if settings.general.use_sonarr:
             try:
-                sv = url_sonarr() + "/api/system/status?apikey=" + settings.sonarr.apikey
-                sonarr_json = requests.get(sv, timeout=int(settings.sonarr.http_timeout), verify=False, headers=headers).json()
+                sv = f"{url_sonarr()}/api/system/status?apikey={settings.sonarr.apikey}"
+                sonarr_json = requests.get(sv, timeout=int(settings.sonarr.http_timeout), verify=False,
+                                           headers=headers).json()
                 if 'version' in sonarr_json:
                     sonarr_version = sonarr_json['version']
                 else:
                     raise json.decoder.JSONDecodeError
             except json.decoder.JSONDecodeError:
                 try:
-                    sv = url_sonarr() + "/api/v3/system/status?apikey=" + settings.sonarr.apikey
-                    sonarr_version = requests.get(sv, timeout=int(settings.sonarr.http_timeout), verify=False, headers=headers).json()['version']
+                    sv = f"{url_sonarr()}/api/v3/system/status?apikey={settings.sonarr.apikey}"
+                    sonarr_version = requests.get(sv, timeout=int(settings.sonarr.http_timeout), verify=False,
+                                                  headers=headers).json()['version']
                 except json.decoder.JSONDecodeError:
                     logging.debug('BAZARR cannot get Sonarr version')
                     sonarr_version = 'unknown'
             except Exception:
                 logging.debug('BAZARR cannot get Sonarr version')
                 sonarr_version = 'unknown'
-        logging.debug('BAZARR got this Sonarr version from its API: {}'.format(sonarr_version))
+        logging.debug(f'BAZARR got this Sonarr version from its API: {sonarr_version}')
         region.set("sonarr_version", sonarr_version)
         return sonarr_version
 
@@ -83,7 +85,7 @@ def url_sonarr():
     if settings.sonarr.base_url == '':
         settings.sonarr.base_url = "/"
     if not settings.sonarr.base_url.startswith("/"):
-        settings.sonarr.base_url = "/" + settings.sonarr.base_url
+        settings.sonarr.base_url = f"/{settings.sonarr.base_url}"
     if settings.sonarr.base_url.endswith("/"):
         settings.sonarr.base_url = settings.sonarr.base_url[:-1]
 
diff --git a/bazarr/sonarr/notify.py b/bazarr/sonarr/notify.py
index c6d004091..66b3096b4 100644
--- a/bazarr/sonarr/notify.py
+++ b/bazarr/sonarr/notify.py
@@ -11,9 +11,9 @@
 def notify_sonarr(sonarr_series_id):
     try:
         if get_sonarr_info.is_legacy():
-            url = url_sonarr() + "/api/command?apikey=" + settings.sonarr.apikey
+            url = f"{url_sonarr()}/api/command?apikey={settings.sonarr.apikey}"
         else:
-            url = url_sonarr() + "/api/v3/command?apikey=" + settings.sonarr.apikey
+            url = f"{url_sonarr()}/api/v3/command?apikey={settings.sonarr.apikey}"
         data = {
             'name': 'RescanSeries',
             'seriesId': int(sonarr_series_id)
diff --git a/bazarr/sonarr/rootfolder.py b/bazarr/sonarr/rootfolder.py
index 6352e7251..3a0b9032a 100644
--- a/bazarr/sonarr/rootfolder.py
+++ b/bazarr/sonarr/rootfolder.py
@@ -17,9 +17,9 @@ def get_sonarr_rootfolder():
 
     # Get root folder data from Sonarr
     if get_sonarr_info.is_legacy():
-        url_sonarr_api_rootfolder = url_sonarr() + "/api/rootfolder?apikey=" + apikey_sonarr
+        url_sonarr_api_rootfolder = f"{url_sonarr()}/api/rootfolder?apikey={apikey_sonarr}"
     else:
-        url_sonarr_api_rootfolder = url_sonarr() + "/api/v3/rootfolder?apikey=" + apikey_sonarr
+        url_sonarr_api_rootfolder = f"{url_sonarr()}/api/v3/rootfolder?apikey={apikey_sonarr}"
 
     try:
         rootfolder = requests.get(url_sonarr_api_rootfolder, timeout=int(settings.sonarr.http_timeout), verify=False, headers=headers)
diff --git a/bazarr/sonarr/sync/episodes.py b/bazarr/sonarr/sync/episodes.py
index d1f3bc98c..a0e2d0cd8 100644
--- a/bazarr/sonarr/sync/episodes.py
+++ b/bazarr/sonarr/sync/episodes.py
@@ -130,7 +130,7 @@ def sync_episodes(series_id, send_event=True):
 
 
 def sync_one_episode(episode_id, defer_search=False):
-    logging.debug('BAZARR syncing this specific episode from Sonarr: {}'.format(episode_id))
+    logging.debug(f'BAZARR syncing this specific episode from Sonarr: {episode_id}')
     url = url_sonarr()
     apikey_sonarr = settings.sonarr.apikey
 
@@ -173,8 +173,8 @@ def sync_one_episode(episode_id, defer_search=False):
             logging.error(f"BAZARR cannot delete episode {existing_episode.path} because of {e}")
         else:
             event_stream(type='episode', action='delete', payload=int(episode_id))
-            logging.debug('BAZARR deleted this episode from the database:{}'.format(path_mappings.path_replace(
-                existing_episode['path'])))
+            logging.debug(
+                f'BAZARR deleted this episode from the database:{path_mappings.path_replace(existing_episode["path"])}')
         return
 
     # Update existing episodes in DB
@@ -188,8 +188,8 @@ def sync_one_episode(episode_id, defer_search=False):
             logging.error(f"BAZARR cannot update episode {episode['path']} because of {e}")
         else:
             event_stream(type='episode', action='update', payload=int(episode_id))
-            logging.debug('BAZARR updated this episode into the database:{}'.format(path_mappings.path_replace(
-                episode['path'])))
+            logging.debug(
+                f'BAZARR updated this episode into the database:{path_mappings.path_replace(episode["path"])}')
 
     # Insert new episodes in DB
     elif episode and not existing_episode:
@@ -201,19 +201,19 @@ def sync_one_episode(episode_id, defer_search=False):
             logging.error(f"BAZARR cannot insert episode {episode['path']} because of {e}")
         else:
             event_stream(type='episode', action='update', payload=int(episode_id))
-            logging.debug('BAZARR inserted this episode into the database:{}'.format(path_mappings.path_replace(
-                episode['path'])))
+            logging.debug(
+                f'BAZARR inserted this episode into the database:{path_mappings.path_replace(episode["path"])}')
 
     # Storing existing subtitles
-    logging.debug('BAZARR storing subtitles for this episode: {}'.format(path_mappings.path_replace(
-            episode['path'])))
+    logging.debug(f'BAZARR storing subtitles for this episode: {path_mappings.path_replace(episode["path"])}')
     store_subtitles(episode['path'], path_mappings.path_replace(episode['path']))
 
     # Downloading missing subtitles
     if defer_search:
-        logging.debug('BAZARR searching for missing subtitles is deferred until scheduled task execution for this '
-                      'episode: {}'.format(path_mappings.path_replace(episode['path'])))
+        logging.debug(
+            f'BAZARR searching for missing subtitles is deferred until scheduled task execution for this episode: '
+            f'{path_mappings.path_replace(episode["path"])}')
     else:
-        logging.debug('BAZARR downloading missing subtitles for this episode: {}'.format(path_mappings.path_replace(
-            episode['path'])))
+        logging.debug(
+            f'BAZARR downloading missing subtitles for this episode: {path_mappings.path_replace(episode["path"])}')
         episode_download_subtitles(episode_id)
diff --git a/bazarr/sonarr/sync/parser.py b/bazarr/sonarr/sync/parser.py
index 222a21500..ad3fae852 100644
--- a/bazarr/sonarr/sync/parser.py
+++ b/bazarr/sonarr/sync/parser.py
@@ -18,7 +18,7 @@ def seriesParser(show, action, tags_dict, serie_default_profile, audio_profiles)
     for image in show['images']:
         if image['coverType'] == 'poster':
             poster_big = image['url'].split('?')[0]
-            poster = os.path.splitext(poster_big)[0] + '-250' + os.path.splitext(poster_big)[1]
+            poster = f'{os.path.splitext(poster_big)[0]}-250{os.path.splitext(poster_big)[1]}'
 
         if image['coverType'] == 'fanart':
             fanart = image['url'].split('?')[0]
@@ -144,7 +144,7 @@ def episodeParser(episode):
                     except Exception:
                         video_format = episode['episodeFile']['quality']['quality']['name']
                         try:
-                            video_resolution = str(episode['episodeFile']['quality']['quality']['resolution']) + 'p'
+                            video_resolution = f'{episode["episodeFile"]["quality"]["quality"]["resolution"]}p'
                         except Exception:
                             video_resolution = None
 
diff --git a/bazarr/sonarr/sync/series.py b/bazarr/sonarr/sync/series.py
index cb346a178..92c819a71 100644
--- a/bazarr/sonarr/sync/series.py
+++ b/bazarr/sonarr/sync/series.py
@@ -117,7 +117,7 @@ def update_series(send_event=True):
 
 
 def update_one_series(series_id, action):
-    logging.debug('BAZARR syncing this specific series from Sonarr: {}'.format(series_id))
+    logging.debug(f'BAZARR syncing this specific series from Sonarr: {series_id}')
 
     # Check if there's a row in database for this series ID
     existing_series = database.execute(
@@ -180,8 +180,7 @@ def update_one_series(series_id, action):
         else:
             sync_episodes(series_id=int(series_id), send_event=False)
             event_stream(type='series', action='update', payload=int(series_id))
-            logging.debug('BAZARR updated this series into the database:{}'.format(path_mappings.path_replace(
-                series['path'])))
+            logging.debug(f'BAZARR updated this series into the database:{path_mappings.path_replace(series["path"])}')
 
     # Insert new series in DB
     elif action == 'updated' and not existing_series:
@@ -193,5 +192,4 @@ def update_one_series(series_id, action):
             logging.error(f"BAZARR cannot insert series {series['path']} because of {e}")
         else:
             event_stream(type='series', action='update', payload=int(series_id))
-            logging.debug('BAZARR inserted this series into the database:{}'.format(path_mappings.path_replace(
-                series['path'])))
+            logging.debug(f'BAZARR inserted this series into the database:{path_mappings.path_replace(series["path"])}')
diff --git a/bazarr/sonarr/sync/utils.py b/bazarr/sonarr/sync/utils.py
index de13d229e..6b7060514 100644
--- a/bazarr/sonarr/sync/utils.py
+++ b/bazarr/sonarr/sync/utils.py
@@ -14,15 +14,16 @@ def get_profile_list():
 
     # Get profiles data from Sonarr
     if get_sonarr_info.is_legacy():
-        url_sonarr_api_series = url_sonarr() + "/api/profile?apikey=" + apikey_sonarr
+        url_sonarr_api_series = f"{url_sonarr()}/api/profile?apikey={apikey_sonarr}"
     else:
         if not get_sonarr_info.version().startswith('3.'):
             # return an empty list when using Sonarr >= v4 that does not support series languages profiles anymore
             return profiles_list
-        url_sonarr_api_series = url_sonarr() + "/api/v3/languageprofile?apikey=" + apikey_sonarr
+        url_sonarr_api_series = f"{url_sonarr()}/api/v3/languageprofile?apikey={apikey_sonarr}"
 
     try:
-        profiles_json = requests.get(url_sonarr_api_series, timeout=int(settings.sonarr.http_timeout), verify=False, headers=headers)
+        profiles_json = requests.get(url_sonarr_api_series, timeout=int(settings.sonarr.http_timeout), verify=False,
+                                     headers=headers)
     except requests.exceptions.ConnectionError:
         logging.exception("BAZARR Error trying to get profiles from Sonarr. Connection Error.")
         return None
@@ -50,9 +51,9 @@ def get_tags():
 
     # Get tags data from Sonarr
     if get_sonarr_info.is_legacy():
-        url_sonarr_api_series = url_sonarr() + "/api/tag?apikey=" + apikey_sonarr
+        url_sonarr_api_series = f"{url_sonarr()}/api/tag?apikey={apikey_sonarr}"
     else:
-        url_sonarr_api_series = url_sonarr() + "/api/v3/tag?apikey=" + apikey_sonarr
+        url_sonarr_api_series = f"{url_sonarr()}/api/v3/tag?apikey={apikey_sonarr}"
 
     try:
         tagsDict = requests.get(url_sonarr_api_series, timeout=int(settings.sonarr.http_timeout), verify=False, headers=headers)
@@ -70,8 +71,8 @@ def get_tags():
 
 
 def get_series_from_sonarr_api(url, apikey_sonarr, sonarr_series_id=None):
-    url_sonarr_api_series = url + "/api/{0}series/{1}?apikey={2}".format(
-        '' if get_sonarr_info.is_legacy() else 'v3/', sonarr_series_id if sonarr_series_id else "", apikey_sonarr)
+    url_sonarr_api_series = (f"{url}/api/{'' if get_sonarr_info.is_legacy() else 'v3/'}series/"
+                             f"{sonarr_series_id if sonarr_series_id else ''}?apikey={apikey_sonarr}")
     try:
         r = requests.get(url_sonarr_api_series, timeout=int(settings.sonarr.http_timeout), verify=False, headers=headers)
         r.raise_for_status()
@@ -99,11 +100,11 @@ def get_series_from_sonarr_api(url, apikey_sonarr, sonarr_series_id=None):
 
 def get_episodes_from_sonarr_api(url, apikey_sonarr, series_id=None, episode_id=None):
     if series_id:
-        url_sonarr_api_episode = url + "/api/{0}episode?seriesId={1}&apikey={2}".format(
-            '' if get_sonarr_info.is_legacy() else 'v3/', series_id, apikey_sonarr)
+        url_sonarr_api_episode = (f"{url}/api/{'' if get_sonarr_info.is_legacy() else 'v3/'}episode?"
+                                  f"seriesId={series_id}&apikey={apikey_sonarr}")
     elif episode_id:
-        url_sonarr_api_episode = url + "/api/{0}episode/{1}?apikey={2}".format(
-            '' if get_sonarr_info.is_legacy() else 'v3/', episode_id, apikey_sonarr)
+        url_sonarr_api_episode = (f"{url}/api/{'' if get_sonarr_info.is_legacy() else 'v3/'}episode/{episode_id}?"
+                                  f"apikey={apikey_sonarr}")
     else:
         return
 
@@ -128,15 +129,15 @@ def get_episodes_from_sonarr_api(url, apikey_sonarr, series_id=None, episode_id=
 
 def get_episodesFiles_from_sonarr_api(url, apikey_sonarr, series_id=None, episode_file_id=None):
     if series_id:
-        url_sonarr_api_episodeFiles = url + "/api/v3/episodeFile?seriesId={0}&apikey={1}".format(series_id,
-                                                                                                 apikey_sonarr)
+        url_sonarr_api_episodeFiles = f"{url}/api/v3/episodeFile?seriesId={series_id}&apikey={apikey_sonarr}"
     elif episode_file_id:
-        url_sonarr_api_episodeFiles = url + "/api/v3/episodeFile/{0}?apikey={1}".format(episode_file_id, apikey_sonarr)
+        url_sonarr_api_episodeFiles = f"{url}/api/v3/episodeFile/{episode_file_id}?apikey={apikey_sonarr}"
     else:
         return
 
     try:
-        r = requests.get(url_sonarr_api_episodeFiles, timeout=int(settings.sonarr.http_timeout), verify=False, headers=headers)
+        r = requests.get(url_sonarr_api_episodeFiles, timeout=int(settings.sonarr.http_timeout), verify=False,
+                         headers=headers)
         r.raise_for_status()
     except requests.exceptions.HTTPError:
         logging.exception("BAZARR Error trying to get episodeFiles from Sonarr. Http error.")
diff --git a/bazarr/subtitles/download.py b/bazarr/subtitles/download.py
index 6d0aa6a16..9aa4fb88c 100644
--- a/bazarr/subtitles/download.py
+++ b/bazarr/subtitles/download.py
@@ -29,7 +29,7 @@ def generate_subtitles(path, languages, audio_language, sceneName, title, media_
     if not languages:
         return None
 
-    logging.debug('BAZARR Searching subtitles for this file: ' + path)
+    logging.debug(f'BAZARR Searching subtitles for this file: {path}')
 
     if settings.general.utf8_encode:
         os.environ["SZ_KEEP_ENCODING"] = ""
@@ -97,7 +97,7 @@ def generate_subtitles(path, languages, audio_language, sceneName, title, media_
                                                              )
                         except Exception as e:
                             logging.exception(
-                                'BAZARR Error saving Subtitles file to disk for this file:' + path + ': ' + repr(e))
+                                f'BAZARR Error saving Subtitles file to disk for this file {path}: {repr(e)}')
                             pass
                         else:
                             saved_any = True
@@ -115,12 +115,12 @@ def generate_subtitles(path, languages, audio_language, sceneName, title, media_
             return None
 
         if not saved_any:
-            logging.debug('BAZARR No Subtitles were found for this file: ' + path)
+            logging.debug(f'BAZARR No Subtitles were found for this file: {path}')
             return None
 
     subliminal.region.backend.sync()
 
-    logging.debug('BAZARR Ended searching Subtitles for file: ' + path)
+    logging.debug(f'BAZARR Ended searching Subtitles for file: {path}')
 
 
 def _get_language_obj(languages):
diff --git a/bazarr/subtitles/indexer/movies.py b/bazarr/subtitles/indexer/movies.py
index 1a90afcb2..1fa9c0e6c 100644
--- a/bazarr/subtitles/indexer/movies.py
+++ b/bazarr/subtitles/indexer/movies.py
@@ -22,7 +22,7 @@
 
 
 def store_subtitles_movie(original_path, reversed_path, use_cache=True):
-    logging.debug('BAZARR started subtitles indexing for this file: ' + reversed_path)
+    logging.debug(f'BAZARR started subtitles indexing for this file: {reversed_path}')
     actual_subtitles = []
     if os.path.exists(reversed_path):
         if settings.general.use_embedded_subs:
@@ -52,18 +52,18 @@ def store_subtitles_movie(original_path, reversed_path, use_cache=True):
                             if alpha2_from_alpha3(subtitle_language) is not None:
                                 lang = str(alpha2_from_alpha3(subtitle_language))
                                 if subtitle_forced:
-                                    lang = lang + ':forced'
+                                    lang = f'{lang}:forced'
                                 if subtitle_hi:
-                                    lang = lang + ':hi'
-                                logging.debug("BAZARR embedded subtitles detected: " + lang)
+                                    lang = f'{lang}:hi'
+                                logging.debug(f"BAZARR embedded subtitles detected: {lang}")
                                 actual_subtitles.append([lang, None, None])
                         except Exception as error:
-                            logging.debug("BAZARR unable to index this unrecognized language: %s (%s)",
-                                          subtitle_language, error)
+                            logging.debug(f"BAZARR unable to index this unrecognized language: {subtitle_language} "
+                                          f"({error})")
                 except Exception:
                     logging.exception(
-                        "BAZARR error when trying to analyze this %s file: %s" % (os.path.splitext(reversed_path)[1],
-                                                                                  reversed_path))
+                        f"BAZARR error when trying to analyze this {os.path.splitext(reversed_path)[1]} file: "
+                        f"{reversed_path}")
 
         try:
             dest_folder = get_subtitle_destination_folder()
@@ -119,12 +119,12 @@ def store_subtitles_movie(original_path, reversed_path, use_cache=True):
 
                 elif str(language.basename) != 'und':
                     if language.forced:
-                        language_str = str(language)
+                        language_str = f'{language}:forced'
                     elif language.hi:
-                        language_str = str(language) + ':hi'
+                        language_str = f'{language}:hi'
                     else:
                         language_str = str(language)
-                    logging.debug("BAZARR external subtitles detected: " + language_str)
+                    logging.debug(f"BAZARR external subtitles detected: {language_str}")
                     actual_subtitles.append([language_str, path_mappings.path_replace_reverse_movie(subtitle_path),
                                              os.stat(subtitle_path).st_size])
 
@@ -139,14 +139,14 @@ def store_subtitles_movie(original_path, reversed_path, use_cache=True):
 
         for movie in matching_movies:
             if movie:
-                logging.debug("BAZARR storing those languages to DB: " + str(actual_subtitles))
+                logging.debug(f"BAZARR storing those languages to DB: {actual_subtitles}")
                 list_missing_subtitles_movies(no=movie.radarrId)
             else:
-                logging.debug("BAZARR haven't been able to update existing subtitles to DB : " + str(actual_subtitles))
+                logging.debug(f"BAZARR haven't been able to update existing subtitles to DB: {actual_subtitles}")
     else:
         logging.debug("BAZARR this file doesn't seems to exist or isn't accessible.")
 
-    logging.debug('BAZARR ended subtitles indexing for this file: ' + reversed_path)
+    logging.debug(f'BAZARR ended subtitles indexing for this file: {reversed_path}')
 
     return actual_subtitles
 
diff --git a/bazarr/subtitles/indexer/series.py b/bazarr/subtitles/indexer/series.py
index 9add0f6b2..36014fa04 100644
--- a/bazarr/subtitles/indexer/series.py
+++ b/bazarr/subtitles/indexer/series.py
@@ -22,7 +22,7 @@
 
 
 def store_subtitles(original_path, reversed_path, use_cache=True):
-    logging.debug('BAZARR started subtitles indexing for this file: ' + reversed_path)
+    logging.debug(f'BAZARR started subtitles indexing for this file: {reversed_path}')
     actual_subtitles = []
     if os.path.exists(reversed_path):
         if settings.general.use_embedded_subs:
@@ -52,10 +52,10 @@ def store_subtitles(original_path, reversed_path, use_cache=True):
                             if alpha2_from_alpha3(subtitle_language) is not None:
                                 lang = str(alpha2_from_alpha3(subtitle_language))
                                 if subtitle_forced:
-                                    lang = lang + ":forced"
+                                    lang = f"{lang}:forced"
                                 if subtitle_hi:
-                                    lang = lang + ":hi"
-                                logging.debug("BAZARR embedded subtitles detected: " + lang)
+                                    lang = f"{lang}:hi"
+                                logging.debug(f"BAZARR embedded subtitles detected: {lang}")
                                 actual_subtitles.append([lang, None, None])
                         except Exception as error:
                             logging.debug("BAZARR unable to index this unrecognized language: %s (%s)", subtitle_language, error)
@@ -118,12 +118,12 @@ def store_subtitles(original_path, reversed_path, use_cache=True):
 
                 elif str(language.basename) != 'und':
                     if language.forced:
-                        language_str = str(language)
+                        language_str = f'{language}:forced'
                     elif language.hi:
-                        language_str = str(language) + ':hi'
+                        language_str = f'{language}:hi'
                     else:
                         language_str = str(language)
-                    logging.debug("BAZARR external subtitles detected: " + language_str)
+                    logging.debug(f"BAZARR external subtitles detected: {language_str}")
                     actual_subtitles.append([language_str, path_mappings.path_replace_reverse(subtitle_path),
                                              os.stat(subtitle_path).st_size])
 
@@ -138,14 +138,14 @@ def store_subtitles(original_path, reversed_path, use_cache=True):
 
         for episode in matching_episodes:
             if episode:
-                logging.debug("BAZARR storing those languages to DB: " + str(actual_subtitles))
+                logging.debug(f"BAZARR storing those languages to DB: {actual_subtitles}")
                 list_missing_subtitles(epno=episode.sonarrEpisodeId)
             else:
-                logging.debug("BAZARR haven't been able to update existing subtitles to DB : " + str(actual_subtitles))
+                logging.debug(f"BAZARR haven't been able to update existing subtitles to DB: {actual_subtitles}")
     else:
         logging.debug("BAZARR this file doesn't seems to exist or isn't accessible.")
 
-    logging.debug('BAZARR ended subtitles indexing for this file: ' + reversed_path)
+    logging.debug(f'BAZARR ended subtitles indexing for this file: {reversed_path}')
 
     return actual_subtitles
 
diff --git a/bazarr/subtitles/indexer/utils.py b/bazarr/subtitles/indexer/utils.py
index 79d7b3a2f..1d9435a41 100644
--- a/bazarr/subtitles/indexer/utils.py
+++ b/bazarr/subtitles/indexer/utils.py
@@ -69,8 +69,8 @@ def guess_external_subtitles(dest_folder, subtitles, media_type, previously_inde
 
                 # to improve performance, skip detection of files larger that 1M
                 if os.path.getsize(subtitle_path) > 1 * 1024 * 1024:
-                    logging.debug("BAZARR subtitles file is too large to be text based. Skipping this file: " +
-                                  subtitle_path)
+                    logging.debug(f"BAZARR subtitles file is too large to be text based. Skipping this file: "
+                                  f"{subtitle_path}")
                     continue
 
                 with open(subtitle_path, 'rb') as f:
@@ -80,8 +80,8 @@ def guess_external_subtitles(dest_folder, subtitles, media_type, previously_inde
                 if encoding and 'encoding' in encoding and encoding['encoding']:
                     encoding = detect(text)['encoding']
                 else:
-                    logging.debug("BAZARR skipping this subtitles because we can't guess the encoding. "
-                                  "It's probably a binary file: " + subtitle_path)
+                    logging.debug(f"BAZARR skipping this subtitles because we can't guess the encoding. "
+                                  f"It's probably a binary file: {subtitle_path}")
                     continue
                 text = text.decode(encoding)
 
@@ -97,8 +97,7 @@ def guess_external_subtitles(dest_folder, subtitles, media_type, previously_inde
                         detected_language = 'zt'
 
                 if detected_language:
-                    logging.debug("BAZARR external subtitles detected and guessed this language: " + str(
-                        detected_language))
+                    logging.debug(f"BAZARR external subtitles detected and guessed this language: {detected_language}")
                     try:
                         subtitles[subtitle] = Language.rebuild(Language.fromietf(detected_language), forced=forced,
                                                                hi=False)
@@ -121,8 +120,8 @@ def guess_external_subtitles(dest_folder, subtitles, media_type, previously_inde
             if os.path.exists(subtitle_path) and os.path.splitext(subtitle_path)[1] in core.SUBTITLE_EXTENSIONS:
                 # to improve performance, skip detection of files larger that 1M
                 if os.path.getsize(subtitle_path) > 1 * 1024 * 1024:
-                    logging.debug("BAZARR subtitles file is too large to be text based. Skipping this file: " +
-                                  subtitle_path)
+                    logging.debug(f"BAZARR subtitles file is too large to be text based. Skipping this file: "
+                                  f"{subtitle_path}")
                     continue
 
                 with open(subtitle_path, 'rb') as f:
@@ -132,8 +131,8 @@ def guess_external_subtitles(dest_folder, subtitles, media_type, previously_inde
                 if encoding and 'encoding' in encoding and encoding['encoding']:
                     encoding = detect(text)['encoding']
                 else:
-                    logging.debug("BAZARR skipping this subtitles because we can't guess the encoding. "
-                                  "It's probably a binary file: " + subtitle_path)
+                    logging.debug(f"BAZARR skipping this subtitles because we can't guess the encoding. "
+                                  f"It's probably a binary file: {subtitle_path}")
                     continue
                 text = text.decode(encoding)
 
diff --git a/bazarr/subtitles/manual.py b/bazarr/subtitles/manual.py
index ca454e7ee..7fd91dd33 100644
--- a/bazarr/subtitles/manual.py
+++ b/bazarr/subtitles/manual.py
@@ -25,7 +25,7 @@
 
 @update_pools
 def manual_search(path, profile_id, providers, sceneName, title, media_type):
-    logging.debug('BAZARR Manually searching subtitles for this file: ' + path)
+    logging.debug(f'BAZARR Manually searching subtitles for this file: {path}')
 
     final_subtitles = []
 
@@ -64,7 +64,7 @@ def manual_search(path, profile_id, providers, sceneName, title, media_type):
                 logging.info("BAZARR All providers are throttled")
                 return 'All providers are throttled'
         except Exception:
-            logging.exception("BAZARR Error trying to get Subtitle list from provider for this file: " + path)
+            logging.exception(f"BAZARR Error trying to get Subtitle list from provider for this file: {path}")
         else:
             subtitles_list = []
             minimum_score = settings.general.minimum_score
@@ -145,8 +145,8 @@ def manual_search(path, profile_id, providers, sceneName, title, media_type):
 
             final_subtitles = sorted(subtitles_list, key=lambda x: (x['orig_score'], x['score_without_hash']),
                                      reverse=True)
-            logging.debug('BAZARR ' + str(len(final_subtitles)) + " Subtitles have been found for this file: " + path)
-            logging.debug('BAZARR Ended searching Subtitles for this file: ' + path)
+            logging.debug(f'BAZARR {len(final_subtitles)} Subtitles have been found for this file: {path}')
+            logging.debug(f'BAZARR Ended searching Subtitles for this file: {path}')
 
     subliminal.region.backend.sync()
 
@@ -156,7 +156,7 @@ def manual_search(path, profile_id, providers, sceneName, title, media_type):
 @update_pools
 def manual_download_subtitle(path, audio_language, hi, forced, subtitle, provider, sceneName, title, media_type,
                              use_original_format, profile_id):
-    logging.debug('BAZARR Manually downloading Subtitles for this file: ' + path)
+    logging.debug(f'BAZARR Manually downloading Subtitles for this file: {path}')
 
     if settings.general.utf8_encode:
         os.environ["SZ_KEEP_ENCODING"] = ""
@@ -180,16 +180,16 @@ def manual_download_subtitle(path, audio_language, hi, forced, subtitle, provide
         try:
             if provider:
                 download_subtitles([subtitle], _get_pool(media_type, profile_id))
-                logging.debug('BAZARR Subtitles file downloaded for this file:' + path)
+                logging.debug(f'BAZARR Subtitles file downloaded for this file: {path}')
             else:
                 logging.info("BAZARR All providers are throttled")
                 return 'All providers are throttled'
         except Exception:
-            logging.exception('BAZARR Error downloading Subtitles for this file ' + path)
+            logging.exception(f'BAZARR Error downloading Subtitles for this file {path}')
             return 'Error downloading Subtitles'
         else:
             if not subtitle.is_valid():
-                logging.exception('BAZARR No valid Subtitles file found for this file: ' + path)
+                logging.exception(f'BAZARR No valid Subtitles file found for this file: {path}')
                 return 'No valid Subtitles file found'
             try:
                 chmod = int(settings.general.chmod, 8) if not sys.platform.startswith(
@@ -202,7 +202,7 @@ def manual_download_subtitle(path, audio_language, hi, forced, subtitle, provide
                                                  formats=(subtitle.format,),
                                                  path_decoder=force_unicode)
             except Exception:
-                logging.exception('BAZARR Error saving Subtitles file to disk for this file:' + path)
+                logging.exception(f'BAZARR Error saving Subtitles file to disk for this file: {path}')
                 return 'Error saving Subtitles file to disk'
             else:
                 if saved_subtitles:
@@ -218,14 +218,14 @@ def manual_download_subtitle(path, audio_language, hi, forced, subtitle, provide
                             continue
                 else:
                     logging.error(
-                        "BAZARR Tried to manually download a Subtitles for file: " + path
-                        + " but we weren't able to do (probably throttled by " + str(subtitle.provider_name)
-                        + ". Please retry later or select a Subtitles from another provider.")
+                        f"BAZARR Tried to manually download a Subtitles for file: {path} but we weren't able to do "
+                        f"(probably throttled by {subtitle.provider_name}. Please retry later or select a Subtitles "
+                        f"from another provider.")
                     return 'Something went wrong, check the logs for error'
 
     subliminal.region.backend.sync()
 
-    logging.debug('BAZARR Ended manually downloading Subtitles for file: ' + path)
+    logging.debug(f'BAZARR Ended manually downloading Subtitles for file: {path}')
 
 
 def _get_language_obj(profile_id):
diff --git a/bazarr/subtitles/mass_download/movies.py b/bazarr/subtitles/mass_download/movies.py
index fee57b2dd..25fa04364 100644
--- a/bazarr/subtitles/mass_download/movies.py
+++ b/bazarr/subtitles/mass_download/movies.py
@@ -67,7 +67,7 @@ def movies_download_subtitles(no):
             logging.info("BAZARR All providers are throttled")
             break
 
-    show_progress(id='movie_search_progress_{}'.format(no),
+    show_progress(id=f'movie_search_progress_{no}',
                   header='Searching missing subtitles...',
                   name=movie.title,
                   value=0,
@@ -88,4 +88,4 @@ def movies_download_subtitles(no):
             history_log_movie(1, no, result)
             send_notifications_movie(no, result.message)
 
-    hide_progress(id='movie_search_progress_{}'.format(no))
+    hide_progress(id=f'movie_search_progress_{no}')
diff --git a/bazarr/subtitles/mass_download/series.py b/bazarr/subtitles/mass_download/series.py
index 43d85cfd6..3a9d998ca 100644
--- a/bazarr/subtitles/mass_download/series.py
+++ b/bazarr/subtitles/mass_download/series.py
@@ -49,8 +49,8 @@ def series_download_subtitles(no):
         .where(reduce(operator.and_, conditions))) \
         .all()
     if not episodes_details:
-        logging.debug("BAZARR no episode for that sonarrSeriesId have been found in database or they have all been "
-                      "ignored because of monitored status, series type or series tags: {}".format(no))
+        logging.debug(f"BAZARR no episode for that sonarrSeriesId have been found in database or they have all been "
+                      f"ignored because of monitored status, series type or series tags: {no}")
         return
 
     count_episodes_details = len(episodes_details)
@@ -59,12 +59,9 @@ def series_download_subtitles(no):
         providers_list = get_providers()
 
         if providers_list:
-            show_progress(id='series_search_progress_{}'.format(no),
+            show_progress(id=f'series_search_progress_{no}',
                           header='Searching missing subtitles...',
-                          name='{0} - S{1:02d}E{2:02d} - {3}'.format(episode.title,
-                                                                     episode.season,
-                                                                     episode.episode,
-                                                                     episode.episodeTitle),
+                          name=f'{episode.title} - S{episode.season:02d}E{episode.episode:02d} - {episode.episodeTitle}',
                           value=i,
                           count=count_episodes_details)
 
@@ -101,7 +98,7 @@ def series_download_subtitles(no):
             logging.info("BAZARR All providers are throttled")
             break
 
-    hide_progress(id='series_search_progress_{}'.format(no))
+    hide_progress(id=f'series_search_progress_{no}')
 
 
 def episode_download_subtitles(no, send_progress=False):
@@ -134,12 +131,9 @@ def episode_download_subtitles(no, send_progress=False):
 
         if providers_list:
             if send_progress:
-                show_progress(id='episode_search_progress_{}'.format(no),
+                show_progress(id=f'episode_search_progress_{no}',
                               header='Searching missing subtitles...',
-                              name='{0} - S{1:02d}E{2:02d} - {3}'.format(episode.title,
-                                                                         episode.season,
-                                                                         episode.episode,
-                                                                         episode.episodeTitle),
+                              name=f'{episode.title} - S{episode.season:02d}E{episode.episode:02d} - {episode.episodeTitle}',
                               value=0,
                               count=1)
 
@@ -174,7 +168,7 @@ def episode_download_subtitles(no, send_progress=False):
                     send_notifications(episode.sonarrSeriesId, episode.sonarrEpisodeId, result.message)
 
             if send_progress:
-                hide_progress(id='episode_search_progress_{}'.format(no))
+                hide_progress(id=f'episode_search_progress_{no}')
         else:
             logging.info("BAZARR All providers are throttled")
             break
diff --git a/bazarr/subtitles/post_processing.py b/bazarr/subtitles/post_processing.py
index 472c53201..87704df52 100644
--- a/bazarr/subtitles/post_processing.py
+++ b/bazarr/subtitles/post_processing.py
@@ -26,13 +26,13 @@ def postprocessing(command, path):
         out = out.replace('\n', ' ').replace('\r', ' ')
 
     except Exception as e:
-        logging.error('BAZARR Post-processing failed for file ' + path + ' : ' + repr(e))
+        logging.error(f'BAZARR Post-processing failed for file {path}: {repr(e)}')
     else:
         if err:
-            logging.error(
-                'BAZARR Post-processing result for file ' + path + ' : ' + err.replace('\n', ' ').replace('\r', ' '))
+            parsed_err = err.replace('\n', ' ').replace('\r', ' ')
+            logging.error(f'BAZARR Post-processing result for file {path}: {parsed_err}')
         elif out == "":
             logging.info(
-                'BAZARR Post-processing result for file ' + path + ' : Nothing returned from command execution')
+                f'BAZARR Post-processing result for file {path}: Nothing returned from command execution')
         else:
-            logging.info('BAZARR Post-processing result for file ' + path + ' : ' + out)
+            logging.info(f'BAZARR Post-processing result for file {path}: {out}')
diff --git a/bazarr/subtitles/processing.py b/bazarr/subtitles/processing.py
index bc0ada4e3..9325d1904 100644
--- a/bazarr/subtitles/processing.py
+++ b/bazarr/subtitles/processing.py
@@ -31,9 +31,9 @@ def __init__(self, message, reversed_path, downloaded_language_code2, downloaded
         self.not_matched = not_matched
 
         if hearing_impaired:
-            self.language_code = downloaded_language_code2 + ":hi"
+            self.language_code = f"{downloaded_language_code2}:hi"
         elif forced:
-            self.language_code = downloaded_language_code2 + ":forced"
+            self.language_code = f"{downloaded_language_code2}:forced"
         else:
             self.language_code = downloaded_language_code2
 
@@ -57,7 +57,7 @@ def process_subtitle(subtitle, media_type, audio_language, path, max_score, is_u
         modifier_string = " forced"
     else:
         modifier_string = ""
-    logging.debug('BAZARR Subtitles file saved to disk: ' + downloaded_path)
+    logging.debug(f'BAZARR Subtitles file saved to disk: {downloaded_path}')
     if is_upgrade:
         action = "upgraded"
     elif is_manual:
@@ -66,8 +66,8 @@ def process_subtitle(subtitle, media_type, audio_language, path, max_score, is_u
         action = "downloaded"
 
     percent_score = round(subtitle.score * 100 / max_score, 2)
-    message = downloaded_language + modifier_string + " subtitles " + action + " from " + \
-        downloaded_provider + " with a score of " + str(percent_score) + "%."
+    message = (f"{downloaded_language}{modifier_string} subtitles {action} from {downloaded_provider} with a score of "
+               f"{percent_score}%.")
 
     if media_type == 'series':
         episode_metadata = database.execute(
@@ -116,12 +116,12 @@ def process_subtitle(subtitle, media_type, audio_language, path, max_score, is_u
             pp_threshold = int(settings.general.postprocessing_threshold_movie)
 
         if not use_pp_threshold or (use_pp_threshold and percent_score < pp_threshold):
-            logging.debug("BAZARR Using post-processing command: {}".format(command))
+            logging.debug(f"BAZARR Using post-processing command: {command}")
             postprocessing(command, path)
             set_chmod(subtitles_path=downloaded_path)
         else:
-            logging.debug("BAZARR post-processing skipped because subtitles score isn't below this "
-                          "threshold value: " + str(pp_threshold) + "%")
+            logging.debug(f"BAZARR post-processing skipped because subtitles score isn't below this "
+                          f"threshold value: {pp_threshold}%")
 
     if media_type == 'series':
         reversed_path = path_mappings.path_replace_reverse(path)
diff --git a/bazarr/subtitles/refiners/ffprobe.py b/bazarr/subtitles/refiners/ffprobe.py
index fb792e49a..3fc21bd92 100644
--- a/bazarr/subtitles/refiners/ffprobe.py
+++ b/bazarr/subtitles/refiners/ffprobe.py
@@ -33,7 +33,7 @@ def refine_from_ffprobe(path, video):
                                     episode_file_id=file_id.episode_file_id)
 
     if not data or ('ffprobe' not in data and 'mediainfo' not in data):
-        logging.debug("No cache available for this file: {}".format(path))
+        logging.debug(f"No cache available for this file: {path}")
         return video
 
     if data['ffprobe']:
diff --git a/bazarr/subtitles/sync.py b/bazarr/subtitles/sync.py
index 21025fe79..bcdf37aff 100644
--- a/bazarr/subtitles/sync.py
+++ b/bazarr/subtitles/sync.py
@@ -32,6 +32,6 @@ def sync_subtitles(video_path, srt_path, srt_lang, forced, media_type, percent_s
             gc.collect()
             return True
         else:
-            logging.debug("BAZARR subsync skipped because subtitles score isn't below this "
-                          "threshold value: " + subsync_threshold + "%")
+            logging.debug(f"BAZARR subsync skipped because subtitles score isn't below this "
+                          f"threshold value: {subsync_threshold}%")
     return False
diff --git a/bazarr/subtitles/tools/delete.py b/bazarr/subtitles/tools/delete.py
index 622cf965a..8291c2ff9 100644
--- a/bazarr/subtitles/tools/delete.py
+++ b/bazarr/subtitles/tools/delete.py
@@ -36,7 +36,7 @@ def delete_subtitles(media_type, language, forced, hi, media_path, subtitles_pat
         language_log += ':forced'
         language_string += ' forced'
 
-    result = ProcessSubtitlesResult(message=language_string + " subtitles deleted from disk.",
+    result = ProcessSubtitlesResult(message=f"{language_string} subtitles deleted from disk.",
                                     reversed_path=path_mappings.path_replace_reverse(media_path),
                                     downloaded_language_code2=language_log,
                                     downloaded_provider=None,
@@ -50,7 +50,7 @@ def delete_subtitles(media_type, language, forced, hi, media_path, subtitles_pat
         try:
             os.remove(path_mappings.path_replace(subtitles_path))
         except OSError:
-            logging.exception('BAZARR cannot delete subtitles file: ' + subtitles_path)
+            logging.exception(f'BAZARR cannot delete subtitles file: {subtitles_path}')
             store_subtitles(path_mappings.path_replace_reverse(media_path), media_path)
             return False
         else:
@@ -64,7 +64,7 @@ def delete_subtitles(media_type, language, forced, hi, media_path, subtitles_pat
         try:
             os.remove(path_mappings.path_replace_movie(subtitles_path))
         except OSError:
-            logging.exception('BAZARR cannot delete subtitles file: ' + subtitles_path)
+            logging.exception(f'BAZARR cannot delete subtitles file: {subtitles_path}')
             store_subtitles_movie(path_mappings.path_replace_reverse_movie(media_path), media_path)
             return False
         else:
diff --git a/bazarr/subtitles/tools/mods.py b/bazarr/subtitles/tools/mods.py
index 12c9bc6b0..aeaa28524 100644
--- a/bazarr/subtitles/tools/mods.py
+++ b/bazarr/subtitles/tools/mods.py
@@ -26,7 +26,7 @@ def subtitles_apply_mods(language, subtitle_path, mods, use_original_format, vid
         sub.content = f.read()
 
     if not sub.is_valid():
-        logging.exception('BAZARR Invalid subtitle file: ' + subtitle_path)
+        logging.exception(f'BAZARR Invalid subtitle file: {subtitle_path}')
         return
 
     if use_original_format:
diff --git a/bazarr/subtitles/tools/subsyncer.py b/bazarr/subtitles/tools/subsyncer.py
index e3f8f6943..cee72dd5d 100644
--- a/bazarr/subtitles/tools/subsyncer.py
+++ b/bazarr/subtitles/tools/subsyncer.py
@@ -34,7 +34,7 @@ def sync(self, video_path, srt_path, srt_lang, media_type, sonarr_series_id=None
              radarr_id=None):
         self.reference = video_path
         self.srtin = srt_path
-        self.srtout = '{}.synced.srt'.format(os.path.splitext(self.srtin)[0])
+        self.srtout = f'{os.path.splitext(self.srtin)[0]}.synced.srt'
         self.args = None
 
         ffprobe_exe = get_binary('ffprobe')
@@ -68,8 +68,8 @@ def sync(self, video_path, srt_path, srt_lang, media_type, sonarr_series_id=None
         try:
             result = run(self.args)
         except Exception:
-            logging.exception('BAZARR an exception occurs during the synchronization process for this subtitles: '
-                              '{0}'.format(self.srtin))
+            logging.exception(
+                f'BAZARR an exception occurs during the synchronization process for this subtitles: {self.srtin}')
             raise OSError
         else:
             if settings.subsync.debug:
@@ -81,9 +81,9 @@ def sync(self, video_path, srt_path, srt_lang, media_type, sonarr_series_id=None
 
                     offset_seconds = result['offset_seconds'] or 0
                     framerate_scale_factor = result['framerate_scale_factor'] or 0
-                    message = "{0} subtitles synchronization ended with an offset of {1} seconds and a framerate " \
-                              "scale factor of {2}.".format(language_from_alpha2(srt_lang), offset_seconds,
-                                                            "{:.2f}".format(framerate_scale_factor))
+                    message = (f"{language_from_alpha2(srt_lang)} subtitles synchronization ended with an offset of "
+                               f"{offset_seconds} seconds and a framerate scale factor of "
+                               f"{f'{framerate_scale_factor:.2f}'}.")
 
                     result = ProcessSubtitlesResult(message=message,
                                                     reversed_path=path_mappings.path_replace_reverse(self.reference),
@@ -101,6 +101,6 @@ def sync(self, video_path, srt_path, srt_lang, media_type, sonarr_series_id=None
                     else:
                         history_log_movie(action=5, radarr_id=radarr_id, result=result)
             else:
-                logging.error('BAZARR unable to sync subtitles: {0}'.format(self.srtin))
+                logging.error(f'BAZARR unable to sync subtitles: {self.srtin}')
 
             return result
diff --git a/bazarr/subtitles/tools/translate.py b/bazarr/subtitles/tools/translate.py
index 1761ac50a..d91c6a4ba 100644
--- a/bazarr/subtitles/tools/translate.py
+++ b/bazarr/subtitles/tools/translate.py
@@ -31,7 +31,7 @@ def translate_subtitles_file(video_path, source_srt_file, from_lang, to_lang, fo
     if hi:
         lang_obj = Language.rebuild(lang_obj, hi=True)
 
-    logging.debug('BAZARR is translating in {0} this subtitles {1}'.format(lang_obj, source_srt_file))
+    logging.debug(f'BAZARR is translating in {lang_obj} this subtitles {source_srt_file}')
 
     max_characters = 5000
 
@@ -46,7 +46,7 @@ def translate_subtitles_file(video_path, source_srt_file, from_lang, to_lang, fo
     lines_list = [x.plaintext for x in subs]
     joined_lines_str = '\n\n\n'.join(lines_list)
 
-    logging.debug('BAZARR splitting subtitles into {} characters blocks'.format(max_characters))
+    logging.debug(f'BAZARR splitting subtitles into {max_characters} characters blocks')
     lines_block_list = []
     translated_lines_list = []
     while len(joined_lines_str):
@@ -60,7 +60,7 @@ def translate_subtitles_file(video_path, source_srt_file, from_lang, to_lang, fo
         lines_block_list.append(new_partial_lines_str)
         joined_lines_str = joined_lines_str.replace(new_partial_lines_str, '')
 
-    logging.debug('BAZARR is sending {} blocks to Google Translate'.format(len(lines_block_list)))
+    logging.debug(f'BAZARR is sending {len(lines_block_list)} blocks to Google Translate')
     for block_str in lines_block_list:
         try:
             translated_partial_srt_text = GoogleTranslator(source='auto',
@@ -74,7 +74,7 @@ def translate_subtitles_file(video_path, source_srt_file, from_lang, to_lang, fo
             translated_partial_srt_list = translated_partial_srt_text.split('\n\n\n')
             translated_lines_list += translated_partial_srt_list
 
-    logging.debug('BAZARR saving translated subtitles to {}'.format(dest_srt_file))
+    logging.debug(f'BAZARR saving translated subtitles to {dest_srt_file}')
     for i, line in enumerate(subs):
         try:
             line.plaintext = translated_lines_list[i]
diff --git a/bazarr/subtitles/upgrade.py b/bazarr/subtitles/upgrade.py
index b2aa6bd76..eb072b500 100644
--- a/bazarr/subtitles/upgrade.py
+++ b/bazarr/subtitles/upgrade.py
@@ -87,10 +87,7 @@ def upgrade_subtitles():
 
             show_progress(id='upgrade_episodes_progress',
                           header='Upgrading episodes subtitles...',
-                          name='{0} - S{1:02d}E{2:02d} - {3}'.format(episode['seriesTitle'],
-                                                                     episode['season'],
-                                                                     episode['episode'],
-                                                                     episode['title']),
+                          name=f'{episode["seriesTitle"]} - S{episode["season"]:02d}E{episode["episode"]:02d} - {episode["title"]}',
                           value=i,
                           count=count_episode_to_upgrade)
 
@@ -323,10 +320,10 @@ def _language_from_items(items):
     results = []
     for item in items:
         if item['forced'] == 'True':
-            results.append(item['language'] + ':forced')
+            results.append(f'{item["language"]}:forced')
         elif item['hi'] == 'True':
-            results.append(item['language'] + ':hi')
+            results.append(f'{item["language"]}:hi')
         else:
             results.append(item['language'])
-            results.append(item['language'] + ':hi')
+            results.append(f'{item["language"]}:hi')
     return results
diff --git a/bazarr/subtitles/upload.py b/bazarr/subtitles/upload.py
index f721ec6dd..103ec01ff 100644
--- a/bazarr/subtitles/upload.py
+++ b/bazarr/subtitles/upload.py
@@ -84,7 +84,7 @@ def manual_upload_subtitle(path, language, forced, hi, media_type, subtitle, aud
 
     sub.content = subtitle.read()
     if not sub.is_valid():
-        logging.exception('BAZARR Invalid subtitle file: ' + subtitle.filename)
+        logging.exception(f'BAZARR Invalid subtitle file: {subtitle.filename}')
         sub.mods = None
 
     if settings.general.utf8_encode:
@@ -106,11 +106,11 @@ def manual_upload_subtitle(path, language, forced, hi, media_type, subtitle, aud
                                          formats=(sub.format,) if use_original_format else ("srt",),
                                          path_decoder=force_unicode)
     except Exception:
-        logging.exception('BAZARR Error saving Subtitles file to disk for this file:' + path)
+        logging.exception(f'BAZARR Error saving Subtitles file to disk for this file: {path}')
         return
 
     if len(saved_subtitles) < 1:
-        logging.exception('BAZARR Error saving Subtitles file to disk for this file:' + path)
+        logging.exception(f'BAZARR Error saving Subtitles file to disk for this file: {path}')
         return
 
     subtitle_path = saved_subtitles[0].storage_path
@@ -168,8 +168,8 @@ def manual_upload_subtitle(path, language, forced, hi, media_type, subtitle, aud
         event_stream(type='movie', action='update', payload=movie_metadata.radarrId)
         event_stream(type='movie-wanted', action='delete', payload=movie_metadata.radarrId)
 
-    result = ProcessSubtitlesResult(message=language_from_alpha3(language) + modifier_string + " Subtitles manually "
-                                                                                               "uploaded.",
+    result = ProcessSubtitlesResult(message=f"{language_from_alpha3(language)}{modifier_string} Subtitles manually "
+                                            "uploaded.",
                                     reversed_path=reversed_path,
                                     downloaded_language_code2=uploaded_language_code2,
                                     downloaded_provider=None,
diff --git a/bazarr/subtitles/wanted/series.py b/bazarr/subtitles/wanted/series.py
index 0d7cd2375..4bc687415 100644
--- a/bazarr/subtitles/wanted/series.py
+++ b/bazarr/subtitles/wanted/series.py
@@ -109,10 +109,7 @@ def wanted_search_missing_subtitles_series():
     for i, episode in enumerate(episodes):
         show_progress(id='wanted_episodes_progress',
                       header='Searching subtitles...',
-                      name='{0} - S{1:02d}E{2:02d} - {3}'.format(episode.title,
-                                                                 episode.season,
-                                                                 episode.episode,
-                                                                 episode.episodeTitle),
+                      name=f'{episode.title} - S{episode.season:02d}E{episode.episode:02d} - {episode.episodeTitle}',
                       value=i,
                       count=count_episodes)
 
diff --git a/bazarr/utilities/binaries.py b/bazarr/utilities/binaries.py
index c5efda782..0039e0212 100644
--- a/bazarr/utilities/binaries.py
+++ b/bazarr/utilities/binaries.py
@@ -44,7 +44,7 @@ def get_binary(name):
     installed_exe = which(name)
 
     if installed_exe and os.path.isfile(installed_exe):
-        logging.debug('BAZARR returning this binary: {}'.format(installed_exe))
+        logging.debug(f'BAZARR returning this binary: {installed_exe}')
         return installed_exe
     else:
         logging.debug('BAZARR binary not found in path, searching for it...')
@@ -72,27 +72,27 @@ def get_binary(name):
             logging.debug('BAZARR binary not found in binaries.json')
             raise BinaryNotFound
         else:
-            logging.debug('BAZARR found this in binaries.json: {}'.format(binary))
+            logging.debug(f'BAZARR found this in binaries.json: {binary}')
 
         if os.path.isfile(exe) and md5(exe) == binary['checksum']:
-            logging.debug('BAZARR returning this existing and up-to-date binary: {}'.format(exe))
+            logging.debug(f'BAZARR returning this existing and up-to-date binary: {exe}')
             return exe
         else:
             try:
-                logging.debug('BAZARR creating directory tree for {}'.format(exe_dir))
+                logging.debug(f'BAZARR creating directory tree for {exe_dir}')
                 os.makedirs(exe_dir, exist_ok=True)
-                logging.debug('BAZARR downloading {0} from {1}'.format(name, binary['url']))
+                logging.debug(f'BAZARR downloading {name} from {binary["url"]}')
                 r = requests.get(binary['url'])
-                logging.debug('BAZARR saving {0} to {1}'.format(name, exe_dir))
+                logging.debug(f'BAZARR saving {name} to {exe_dir}')
                 with open(exe, 'wb') as f:
                     f.write(r.content)
                 if system != 'Windows':
-                    logging.debug('BAZARR adding execute permission on {}'.format(exe))
+                    logging.debug(f'BAZARR adding execute permission on {exe}')
                     st = os.stat(exe)
                     os.chmod(exe, st.st_mode | stat.S_IEXEC)
             except Exception:
-                logging.exception('BAZARR unable to download {0} to {1}'.format(name, exe_dir))
+                logging.exception(f'BAZARR unable to download {name} to {exe_dir}')
                 raise BinaryNotFound
             else:
-                logging.debug('BAZARR returning this new binary: {}'.format(exe))
+                logging.debug(f'BAZARR returning this new binary: {exe}')
                 return exe
diff --git a/bazarr/utilities/filesystem.py b/bazarr/utilities/filesystem.py
index 796b510a7..fea29917a 100644
--- a/bazarr/utilities/filesystem.py
+++ b/bazarr/utilities/filesystem.py
@@ -9,7 +9,7 @@ def browse_bazarr_filesystem(path='#'):
         if os.name == 'nt':
             dir_list = []
             for drive in string.ascii_uppercase:
-                drive_letter = drive + ':\\'
+                drive_letter = f'{drive}:\\'
                 if os.path.exists(drive_letter):
                     dir_list.append(drive_letter)
         else:
diff --git a/bazarr/utilities/helper.py b/bazarr/utilities/helper.py
index 5169bd259..fd20f6f3b 100644
--- a/bazarr/utilities/helper.py
+++ b/bazarr/utilities/helper.py
@@ -52,7 +52,7 @@ def get_target_folder(file_path):
             try:
                 os.makedirs(fld)
             except Exception:
-                logging.error('BAZARR is unable to create directory to save subtitles: ' + fld)
+                logging.error(f'BAZARR is unable to create directory to save subtitles: {fld}')
                 fld = None
     else:
         fld = None