URL Encoder & Decoder — Free Percent-Encoding Converter Online
Encode and decode URLs using percent-encoding. Choose between encodeURIComponent and encodeURI modes, with URL component parsing — all in your browser.
Encodes all special chars including / : @ — use for query param values
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Frequently Asked Questions
Q. Why is URL encoding necessary?
URLs can only safely contain alphanumeric characters and a few special symbols. Characters like Korean, spaces, and special symbols must be percent-encoded (%XX) for safe transmission.
Q. What is the difference between encodeURIComponent and encodeURI?
encodeURIComponent encodes URL-structural characters like /, ?, #, = — use it for query parameter values. encodeURI preserves the overall URL structure.
Q. What happens when I encode Korean text?
Korean is first converted to UTF-8 bytes, then each byte is percent-encoded. Example: "안녕" → %EC%95%88%EB%85%95
Q. Does it parse URL structure?
Yes — after decoding, it parses and displays the protocol, host, path, query parameters, and hash.
Q. Is a space encoded as + or %20?
encodeURIComponent encodes spaces as %20. In HTML form data (application/x-www-form-urlencoded), spaces become +.
Q. What does the Swap button do?
It moves the encoded/decoded result back to the input, letting you chain multiple encode/decode operations easily.
How to Use
Input the URL or text you want to encode or decode.
Choose encodeURIComponent (for parameters) or encodeURI (for full URLs).
Click Encode or Decode.
Check the result and URL structure analysis, then copy.
Expert Knowledge: URL Encoder & Decoder — Free Percent-Encoding Converter Online
URL encoding is defined by RFC 3986, which distinguishes reserved characters from unreserved ones. Unreserved characters (letters, digits, -, _, ., ~) need no encoding; everything else is converted to UTF-8 bytes and each byte becomes %XX. Modern browsers handle internationalized domain names (IDN) and non-ASCII paths automatically, but explicit encoding remains essential in API development.
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