URL Encoder & Decoder

URL encoding (percent-encoding) replaces unsafe characters in URLs with a percent sign followed by two hex digits. For example, a space becomes %20 and an ampersand becomes %26. It is needed because URLs can only contain a limited set of ASCII characters. Special characters like spaces, &, =, ?, #, and non-ASCII characters (accents, CJK, emoji) must be encoded to be transmitted correctly. Without encoding, these characters would be misinterpreted as URL syntax — a literal & would be read as a parameter separator instead of data.

encodeURI encodes a full URL string, preserving URL-structural characters like ://?#[]@!$&'()*+,;=. Use it when encoding a complete URL. encodeURIComponent encodes a single URL component value, converting everything except letters, digits, and -_.~. Use it for query parameter values, path segments, and fragment identifiers. Example: to encode the query value 'a=1&b=2', encodeURIComponent produces 'a%3D1%26b%3D2' (safe), while encodeURI produces 'a=1&b=2' (broken, because = and & retain their URL meaning). Always use encodeURIComponent for user-provided data in URLs.

Paste the encoded URL into DevBolt's URL Decoder and it converts percent-encoded sequences back to readable characters. In JavaScript, use decodeURIComponent() for individual values or decodeURI() for full URLs. For example, decodeURIComponent('%E4%BD%A0%E5%A5%BD') returns '你好'. The decoder handles UTF-8 multi-byte sequences, plus signs as spaces (common in form data), and nested encoding. If you see double-encoded URLs like %2520 (where %25 is the encoded percent sign), you may need to decode twice.