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URL Encode / Decode

Percent-encode or decode URLs and query strings.

Runs in your browser — nothing is uploaded

 
 
 
  
 
Why URLs need encoding
 
URLs may only contain a limited set of ASCII characters, and some of those, such as ? & = # / and %, have special meaning. Percent-encoding replaces any other character with % followed by its byte value in hex, so a space becomes %20 and é becomes %C3%A9 (its two UTF-8 bytes).
Without encoding, a value containing & or = would break a query string apart, and a value containing # would cut the URL short at what the browser treats as a fragment.
 
 
Component encoding
 
This tool uses component encoding, the same as JavaScript's encodeURIComponent. It escapes everything except letters, digits and - _ . ! ~ * ' ( ), which makes it the right choice for a single query-string value, a path segment or a form field. Do not run it over a whole URL, because it will also encode the :// and / separators.
Decoding reverses it, turning every %XX sequence back into the original characters. A lone % that is not followed by two hex digits is invalid and is reported as an error rather than guessed at.
 
 
Spaces: %20 or +?
 
HTML form submissions (application/x-www-form-urlencoded) encode spaces as +, while URL paths and encodeURIComponent use %20. Both are common in query strings. If you are decoding a form-encoded value, replace + with a space first.
 
 
Examples
 
 
Encode a query-string value
 
Input
 
name=Ada Lovelace&city=São Paulo
 
Output
 
name%3DAda%20Lovelace%26city%3DS%C3%A3o%20Paulo
 
 
Encode a file name for one path segment
 
Input
 
reports/2026 Q3 (final).pdf
 
Output
 
reports%2F2026%20Q3%20(final).pdf
 
 
Decode an encoded URL
 
Input
 
https%3A%2F%2Fexample.com%2Fsearch%3Fq%3Djson%20formatter
 
Output
 
https://example.com/search?q=json formatter
 
 
 
How to use
 
  1. Paste your text or URL.
  2. Choose Encode or Decode.
  3. Copy the result.
 
 
FAQ
 
 What's the difference between encodeURI and encodeURIComponent? 
encodeURI leaves URL syntax characters such as : / ? & = # intact so a whole URL stays usable. encodeURIComponent escapes them too, for embedding one value inside a URL. This tool uses component encoding.
 
 Why do I get 'Invalid percent-encoding'? 
The input contains a % that is not followed by two hexadecimal digits, or the bytes do not form valid UTF-8. A literal percent sign must itself be encoded as %25.
 
 How do I URL-encode in code? 
In JavaScript, use encodeURIComponent(value). In Python, urllib.parse.quote(value, safe="!*'()") matches it exactly; the default safe='/' would leave slashes unencoded. PHP's rawurlencode($value) is close but also encodes ! * ' ( ).
 
 Which characters never need encoding? 
The unreserved characters: A–Z, a–z, 0–9 and - _ . ~ are safe anywhere in a URL and never need encoding. encodeURIComponent also leaves ! * ' ( ) as they are, which is harmless in almost every context.
 
 
 
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