URL Encode/Decode

URL encoding (percent-encoding) replaces characters that aren't allowed in a URL — spaces, non-Latin letters, special characters — with %XX sequences, where XX is the hex code of the byte. This keeps links and query parameters from getting mangled in transit.

How to use it

• Encode: paste text or a URL and any character outside the safe ASCII set is replaced with a %XX sequence.
• Decode: paste an encoded string to see the original text.
• Encoding a full URL and encoding a single query parameter use slightly different safe-character sets — pick the mode that matches what you're encoding.

Common uses

• Building query parameters from text containing spaces, ampersands, or non-Latin characters.
• Debugging why a link with a parameter breaks — often the cause is an unencoded special character.
• Decoding URLs from third-party systems to read them in their original form.

Things to keep in mind

Encode parameter values, not the whole URL at once — otherwise you'll also encode the separators you need (:, /, ?, &).

JavaScript's encodeURIComponent and encodeURI encode different character sets — the former is meant specifically for parameter values.