diff --git a/wikiteam3/uploader/uploader.py b/wikiteam3/uploader/uploader.py
index f23515c6..94eb6dc0 100644
--- a/wikiteam3/uploader/uploader.py
+++ b/wikiteam3/uploader/uploader.py
@@ -2,9 +2,11 @@
 from datetime import datetime
 import json
 import os
+import random
 import re
 import shutil
 from dataclasses import dataclass
+import sys
 import time
 import traceback
 from typing import Dict, List, Optional, Tuple, Union
@@ -22,6 +24,7 @@
 from wikiteam3.uploader.socketLock import NoLock, SocketLockServer
 from wikiteam3.utils import url2prefix_from_config, sha1sum
 from wikiteam3.uploader.compresser import ZstdCompressor, SevenZipCompressor
+from wikiteam3.utils.ia_checker import ia_s3_tasks_load_avg
 from wikiteam3.utils.util import ALL_DUMPED_MARK, UPLOADED_MARK, mark_as_done, is_markfile_exists
 
 DEFAULT_COLLECTION = 'opensource'
@@ -380,6 +383,26 @@ def upload(arg: Args):
     print("=== Preparing metadata ===")
     metadata, logo_url = prepare_item_metadata(wikidump_dir, config, arg)
 
+    print("=== Checking IA S3 load average (optional) ===")
+
+    try:
+        avg_load = ia_s3_tasks_load_avg(session=item.session) # check IA load
+        print(f"IA S3 load: {avg_load * 100:.4f}%")
+        if avg_load > 0.99:
+            print("WARNING: IA S3 is heavily overloaded, upload may fail")
+            print("Deciding whether to continue even if IA S3 is heavily overloaded... (20% chance to continue, random)")
+            if random.random() < 0.8:
+                print("To prevent IA S3 from being overloaded further, please try uploading later, exiting...")
+                sys.exit(99)
+            print("Continuing anyway...")
+        elif avg_load > 0.9:
+            print("WARNING: IA S3 is overloaded, upload may fail") 
+    except Exception as e:
+        traceback.print_exc()
+        print(f"Failed to get IA S3 load average: {e}")
+        print("Don't worry, it's optional.")
+
+
     if arg.dry_run:
         print("=== Dry run, exiting ===")
         return
diff --git a/wikiteam3/utils/ia_checker.py b/wikiteam3/utils/ia_checker.py
index 818bf6f4..3c208345 100644
--- a/wikiteam3/utils/ia_checker.py
+++ b/wikiteam3/utils/ia_checker.py
@@ -9,6 +9,18 @@
 IA_MAX_RETRY = 5
 logger = logging.getLogger(__name__)
 
+
+def ia_s3_tasks_load_avg(session: ArchiveSession) -> float:
+    api = "https://s3.us.archive.org/?check_limit=1"
+    r = session.get(api, timeout=16)
+    r.raise_for_status()
+    r_json = r.json()
+    total_tasks_queued = r_json["detail"]["total_tasks_queued"]
+    total_global_limit = r_json["detail"]["total_global_limit"]
+    logger.info(f"ia_s3_load_avg(): {total_tasks_queued} / {total_global_limit}")
+    return total_tasks_queued / total_global_limit
+
+
 def search_ia(apiurl: Optional[str] = None, indexurl: Optional[str] = None, addeddate_intervals: Optional[List[str]] = None):
     if apiurl is None:
         apiurl = 'api.php'.join(indexurl.rsplit('index.php', 1)) if indexurl else None