URL Encoder / Decoder

Encode or decode URLs and query strings instantly, safe for transfer over the Internet.

Text to URL Encoded

Encode Full URL (encodeURI vs encodeURIComponent) Batch Mode (Process line-by-line) Double Encode/Decode

Input Text 0 chars

Invalid input string.

Encoded Output 0 chars

What is URL Encoding?

URL Encoding, also known as Percent-encoding, is a mechanism for encoding information in a Uniform Resource Identifier (URI) under certain circumstances. A URL is normally composed of alphanumeric characters and a small number of special characters (such as - _ . ! ~ * ' ( )). If a URL needs to contain other characters—such as spaces, question marks, or ampersands—they must be converted into a valid URL format.

URL encoding works by replacing unsafe ASCII characters with a % followed by two hexadecimal digits that represent the ASCII value of the character. For example, a space character becomes %20.

Why is URL Encoding Important?

URLs are sent over the Internet using the ASCII character-set. Since URLs often contain characters outside the ASCII set, the URL has to be converted into a valid ASCII format. In addition, certain characters have special meanings within a URL, such as ? (which separates the URL from query parameters), & (which separates different query parameters), and = (which separates a parameter name from its value).

If you include these characters as data (rather than as delimiters), they will cause the URL to be interpreted incorrectly by the server. URL encoding ensures that these characters are safely transmitted as data.

encodeURI vs encodeURIComponent

In JavaScript, there are two primary functions for encoding URLs:

encodeURI(): Used to encode an entire URL. It assumes the input is a complete URL and does not encode characters that have special meaning in a URL (like : / ? # & =).
encodeURIComponent(): Used to encode a specific component of a URL, such as a query string parameter. It encodes all characters that could potentially break the URL structure, including the special characters mentioned above. This is the default mode for our tool when the "Encode Full URL" checkbox is unchecked.

Client-Side Security

This URL Encoder/Decoder runs entirely in your web browser. When you paste text, the data is processed locally using JavaScript (using standard encodeURIComponent(), decodeURIComponent() APIs). Your data is never sent to a server, ensuring complete privacy and allowing the tool to work fully offline after the initial page load.