URL Encoder / Decoder Online (Free, In-Browser)

URLs can only safely contain a limited set of characters, so spaces, ampersands and accented letters have to be escaped before they go into a link or query string. That escaping is called percent-encoding. In this guide you will learn how percent-encoding works and how to convert text both ways with the free URL Encoder / Decoder. It handles full Unicode, runs instantly, and processes everything in your browser so nothing you paste is ever uploaded.

What percent-encoding is

Percent-encoding (also called URL encoding) replaces unsafe characters with a percent sign followed by two hexadecimal digits representing the character's byte value. A space, for example, becomes %20.

The rule exists because a URL has reserved characters with special jobs - the question mark starts a query string, the ampersand separates parameters, and the hash marks a fragment. If your actual data contains those characters, they must be encoded so a browser or server does not misread the structure of the URL.

Unicode characters are first converted to their UTF-8 bytes, then each byte is percent-encoded. That is why a single accented letter can turn into two or three percent-escapes. Decoding simply reverses the process to recover the original readable text.

How to use the URL Encoder / Decoder

Converting either direction is quick:

1. Open the URL Encoder / Decoder.
2. Paste the text or URL you want to convert.
3. Choose encode (text to percent-encoded) or decode (percent-encoded back to text).
4. Read the result and copy it with one click.

Use encode when you are building a link or query parameter from raw text, and decode when you have a messy percent-encoded string from a log, a redirect URL or an API response and want to read it. The conversion is instant and there is no limit on length.

Encoding reference table

Here is how some common characters are encoded:

Letters, digits, and a few unreserved marks (hyphen, underscore, dot, tilde) are left as-is. Everything else, including non-English characters, gets percent-encoded based on its UTF-8 bytes.

Use cases

Percent-encoding shows up everywhere on the web:

• Query strings: safely pass a search term that contains spaces or symbols.
• API requests: encode parameter values so special characters do not break the request.
• Redirect URLs: encode a whole URL when passing it as a parameter to another URL.
• Debugging: decode a captured URL to see what data was actually sent.
• Sharing links: clean up a link copied from somewhere that double-encoded it.

For other encoding tasks, the Base64 tool covers binary-to-text encoding, and the HTML Entity Encoder / Decoder handles escaping for markup rather than links.

Tips and common mistakes

Watch out for these:

• Double encoding: encoding an already-encoded string turns %20 into %2520. If a link has stray percent-25 sequences, it was probably encoded twice. Decode once to fix it.
• Encoding a full URL vs a component: encoding an entire URL will escape the slashes and colon too, which you usually do not want. Only encode the individual values you are inserting, like a single query parameter.
• The plus sign: in query strings a plus can mean a space, while in the path it is literal. Be deliberate about which you intend.
• Spaces: always encode spaces in a URL - a raw space will break or get truncated.

When unsure, decode a string first to confirm what it really contains before re-encoding.

Privacy: in-browser conversion

Whatever you paste - a URL with tokens, a query containing personal data, or an internal API path - stays on your machine. The URL Encoder / Decoder performs the conversion in your browser with JavaScript and sends nothing to a server. Nothing is logged or retained.

That means you can safely encode and decode sensitive links during development. Find more instant, private utilities in the dev tools category or across all tools.