URL Encoder & Decoder
Percent-encode or decode URLs and query strings, and inspect parameters.
How to use URL Encoder & Decoder
- Choose Encode or Decode.
- Paste the text, URL or query string.
- Copy the result; for URLs, the query parameters are listed below.
How it works
Percent-encoding (RFC 3986) replaces characters that are not allowed in a URL with % followed by two hex digits of their UTF-8 bytes; a space becomes %20 and "é" becomes %C3%A9.
Component mode encodes everything except letters, digits and -_.~, which is right for a single query value. Full URL keeps the characters that give a URL its structure (:/?#&=). Form mode matches HTML forms, where spaces become +.
Frequently asked questions
Which mode should I use for a query parameter value?
Component mode. Full URL mode would leave & and = unencoded, which breaks the query string.
Why does my decoded text contain + signs?
In HTML form encoding, + means a space. Turn on "Treat + as space" when decoding form data.
What does "malformed" mean?
A % must be followed by two hex digits that form valid UTF-8. A lone % or a cut-off sequence cannot be decoded.
Is anything sent anywhere?
No. Encoding and decoding happen in your browser.
Limitations
- Internationalised domain names (punycode) are not converted.
- Double-encoded text needs decoding twice ("Use result as input").
Last reviewed November 9, 2026. How we build and test tools.