URL Encoder / Decoder
Percent-encode and decode URLs and query strings.
🔒 100% browser-based — your data never leaves your device.
About this tool
URLs can only contain a limited set of ASCII characters, so spaces, non-Latin letters and symbols must be percent-encoded (a space becomes %20, 한 becomes %ED%95%9C). This tool encodes text for safe use in URLs and decodes any percent-encoded string back to readable text.
Two modes are available: component mode (encodeURIComponent) escapes everything including &, = and /, which is right for individual query-string values; URL mode (encodeURI) keeps URL structure characters intact, which is right for encoding a whole address.
Frequently asked questions
When do I use component mode vs URL mode?
Encoding a single value to put after ?q= — use component mode. Encoding a full URL that already has its structure — use URL mode so :, /, ? and & survive.
Why does a space sometimes become + instead of %20?
The + convention comes from old HTML form encoding (application/x-www-form-urlencoded). In modern URLs %20 is the standard; both decode to a space in query strings.
Why do Korean characters become so long?
Each Korean syllable is 3 bytes in UTF-8, and every byte becomes a three-character escape like %ED, so one syllable turns into 9 characters.