diff --git a/lib/index.d.ts b/lib/index.d.ts
new file mode 100644
index 0000000..4610d30
--- /dev/null
+++ b/lib/index.d.ts
@@ -0,0 +1,262 @@
+export interface ParseOptions {
+  /**
+   * By default `parse()` reads a String. 
+   * If you want to read a file, set this option to true. 
+   * If this option is used, the callback is mandatory. 
+   * It gets 2 parameters, a possible error and the object with all the properties.
+   */
+  path?: boolean;
+
+  /**
+   * Allows you to add additional comment tokens. 
+   * The token must be a single printable non-whitespae ascii character. 
+   * If the `strict` option is not set, the tokens `#` and `!` are parsed as comment tokens.
+   * 
+   * @example
+   * comments: ";"
+   * @example
+   * comments: [";", "@"]
+   */
+  comments?: string | string[];
+
+  /**
+   * Allows you to add additional separator tokens. 
+   * The token must be a single printable non-whitespae ascii character. 
+   * If the `strict` option is not set, the tokens `=` and `:` are parsed as comment tokens.
+   * 
+   * @example
+   * separators: "-"
+   * @example
+   * separators: ["-", ">"]
+   */
+  separators?: string | string[];
+
+  /**
+   * This option can be used with the `comments` and `separators` options. 
+   * If true, **only** the tokens specified in these options are used to parse comments and separators.
+   */
+  strict?: boolean;
+
+  /**
+   * Parses INI sections. 
+   * Read the INI section for further details.
+   * 
+   * @link https://www.npmjs.com/package/properties#ini
+   */
+  sections?: boolean;
+
+  /**
+   * Parses dot separated keys as JavaScript objects. 
+   * 
+   * Look at the namespaces section for further details.
+   * @link https://www.npmjs.com/package/properties#namespaces
+   */
+  namespaces?: boolean;
+
+  /**
+   * Allows you to read the value of a key while the file is being parsed. 
+   * 
+   * Look at the variables section for further details.
+   * @link https://www.npmjs.com/package/properties#variables
+   */
+  variables?: boolean;
+
+  /**
+   * External variables can be passed to the file if the variables option is enabled. 
+   * 
+   * Look at the variables section for further details.
+   * @link https://www.npmjs.com/package/properties#variables
+   */
+  vars?: boolean;
+
+  /**
+   * Files can be linked and imported with the include key. 
+   * If this option is used, the callback is mandatory. 
+   * 
+   * Look at the include section for further details.
+   * @link https://www.npmjs.com/package/properties#include
+   */
+  include?: boolean;
+
+  /**
+   * Each property or section can be removed or modified from the final object. 
+   * It's similar to the reviver of the `JSON.parse()` function.
+   * 
+   * The reviver it's exactly the same as the replacer from `stringify()`. 
+   * The same function can be reused.
+   * 
+   * The callback gets 3 parameters: key, value and section.
+   * 
+   * A property has a key and a value and can belong to a section. 
+   * If it's a global property, the section is set to null. 
+   * If **undefined** is returned, the property will be removed from the final object, otherwise the returned value will be used as the property value.
+   * 
+   * If the key and the value are set to null, then it's a section line. 
+   * If it returns a falsy value, it won't be added to the final object, the entire section _including all the properties_ will be discarded. 
+   * If it returns a truthy value, the section is parsed.
+   * 
+   * For your convenience, to know whether the line is a property or section you can access to `this.isProperty` and `this.isSection` from inside the replacer function. 
+   * Also, `this.assert()` can be used to return the default value, the unmodified value that will be used to parse the line.
+   * 
+   * Look at the reviver example for further details.
+   * @link https://github.com/gagle/node-properties/blob/master/examples/reviver/reviver.js
+   */
+  reviver?: (this: Context, key: any, value: any) => any;
+}
+
+export interface Context {
+  readonly isProperty: boolean;
+  readonly isSection: boolean;
+  assert(): any;
+}
+
+/**
+ * Parses a .properties string.
+ * 
+ * @param data 
+ * @param options 
+ */
+export function parse(data: string, options?: ParseOptions): object;
+/**
+ * Parses a .properties string.
+ * 
+ * If a callback is given, the result is returned as the second parameter. Some options will require a callback.
+ * 
+ * @param data 
+ * @param options 
+ * @param cb 
+ */
+export function parse(data: string, options: ParseOptions | undefined, cb: (err: any, result: object | undefined) => void): void;
+
+export interface StringifyOptions {
+  /**
+   * By default `stringify()` returns a string. 
+   * If you want to write it to a file, use this option and pass the path of a file. 
+   * If this option is used, the callback is mandatory. 
+   * It gets two parameters, a possible error and the string.
+   */
+  path?: string;
+
+  /**
+   * The token to use to write comments. 
+   * It must be a single printable non-whitespace ascii character. 
+   * @default `#`
+   */
+  comment?: string;
+
+  /**
+   * The token to use to separate keys from values. 
+   * It must be a single printable non-whitespace ascii character. 
+   * @default `=`
+   */
+  separator?: string;
+
+  /**
+   * The .properties specification uses iso 8859-1 (latin-1) as a default encoding. 
+   * In the other hand, Node.js has a utf8 default encoding. 
+   * This means that if you want a full compatibility with Java, that is, you are generating a .properties file that is going to be read by a Java program, then set this option to true. 
+   * This will encode all ascii extended and multibyte characters to their unicode string representation (`\uXXXX`).
+   * 
+   * Non-printable control codes (control sets 0 and 1) are always encoded as unicode strings except `\t`, `\n`, `\f` and `\r`.
+   * 
+   * If you are in a platform that can handle utf8 strings, e.g. Node.js, you don't need to use this option.
+   */
+  unicode?: boolean;
+
+  /**
+   * Each property or section can be removed or modified from the final string. 
+   * It's similar to the replacer of the `JSON.stringify()` function.
+   * 
+   * The replacer it's exatcly the same as the reviver from `parse()`. 
+   * The same function can be reused.
+   * 
+   * The callback gets three parameters: key, value and section.
+   * 
+   * A property has a key and a value and can belong to a section. 
+   * If it's a global property, the section is set to null. 
+   * If **undefined** is returned, the property won't be stringified, otherwise the returned value will be used as the property value.
+   * 
+   * If the key and the value are set to null, then it's a section line. 
+   * If it returns a falsy value, it won't be added to the final string, the entire section _including all the properties_ will be discarded. 
+   * If it returns a truthy value, the section is stringified.
+   * 
+   * For your convenience, to know whether the line is a property or section you can access to `this.isProperty` and `this.isSection` from inside the replacer function. 
+   * Also, `this.assert()` can be used to return the default value, the unmodified value that will be used to stringify the line.
+   * 
+   * Look at the replacer example for further details.
+   * @link https://github.com/gagle/node-properties/blob/master/examples/replacer.js
+   */
+  replacer?: (this: Context, key: string, value: any) => any;
+}
+
+/**
+ * Stringifies an `object` or a `Stringifier`.
+ * 
+ * If you don't need to add sections or comments simply pass an object, otherwise use a `Stringifier`.
+ * 
+ * @param obj 
+ * @param options 
+ * 
+ * @returns {string}
+ */
+export function stringify(obj: object, options?: StringifyOptions): string;
+
+/**
+ * Stringifies an `object` or a `Stringifier`.
+ * 
+ * If you don't need to add sections or comments simply pass an object, otherwise use a `Stringifier`.
+ * 
+ * The callback is only necessary when the `path` option is used.
+ * 
+ * @param obj 
+ * @param options 
+ * @param cb 
+ */
+export function stringify(obj: object, options: StringifyOptions | undefined, cb: (err: any, result: string) => void): void;
+
+/**
+ * This class is used when you want to add sections or comments to the final string.
+ * 
+ * To create a Stringifier use the `createStringifier()` function.
+ * 
+ * Look at the stringify-ini example for further details.
+ * @link https://github.com/gagle/node-properties/blob/master/examples/ini/stringify-ini.js
+ */
+export interface Stringifier {
+  /**
+   * Writes a header comment. 
+   * It will be written to the top of the final string. 
+   * Returns the Stringifier being used.
+   * 
+   * @returns {Stringifier}
+   */
+  header(comment: string): this;
+
+  /**
+   * Writes a property line. 
+   * It takes an object with three options: `key`, `value` and comment. 
+   * Both the key and the value are converted into a string automatically. 
+   * Returns the Stringifier being used.
+   * 
+   * @returns {Stringifier}
+   */
+  property(obj: { key?: any; value?: any; comment?: string }): this;
+
+  /**
+   * Writes a section line. 
+   * It gets an object with two options: `name` and `comment`. 
+   * The name is converted into a string. 
+   * If you don't need to write a comment, you can pass the name instead of an object. 
+   * Returns the stringifier being used.
+   * 
+   * @returns {Stringifier}
+   */
+  section(obj: string | { name: string; comment?: string }): this;
+}
+
+/**
+ * Returns a new `Stringifier` instance.
+ * 
+ * @returns {Stringifier}
+ */
+export function createStringifier(): Stringifier;
diff --git a/package.json b/package.json
index a741bad..73f6f07 100644
--- a/package.json
+++ b/package.json
@@ -17,5 +17,6 @@
     "test": "node test/parse && node test/stringify"
   },
   "license": "MIT",
-  "main": "lib"
-}
\ No newline at end of file
+  "main": "lib",
+  "typings": "lib/index.d.ts"
+}