How to Encode a URL or URL Component Online

What percent-encoding is for

URLs can only safely contain a narrow set of characters. Spaces, ampersands, question marks and non-ASCII text are ambiguous inside a URL — a space can be mistaken for a separator and an & for a query delimiter. Percent-encoding replaces each unsafe character with a % followed by two hex digits (so a space becomes %20) so the value survives parsing intact.

This tool applies percent-encoding instantly as you type, entirely in your browser, so nothing is uploaded.

Component-level vs whole-URL encoding

There are two distinct jobs. Encoding a query value — say the user input in ?q= — should escape everything except the unreserved characters, using the same rules as JavaScript's encodeURIComponent: A–Z, a–z, 0–9 and - _ . ! ~ * ' ( ) stay unescaped, everything else becomes %hex. This is the default component-level mode.

Encoding a full URL is different: you want the structure to survive, so reserved characters like :, /, ?, & and = should stay intact. That is whole-URL mode (encodeURI). Uncheck Component-level to switch to it.

Encoding and copying

Paste your string into the input area and the output appears immediately — there is nothing to click. Switch the Encode/Decode toggle to flip direction and use 'Use result as input' to re-encode or decode in one step.

Decoding back and avoiding double-encoding

To reverse an encoded string, switch to Decode. If the input contains a bare % that is not part of a valid %hex pair, decoding fails and a red error notice is shown instead of guessing.

Don't re-encode an already encoded value: %20 encoded again becomes %2520, and you have to decode twice to get your original text back. Encode once, at the point of use.