URL Encoder/Decoder — Free Online Percent Encoding Tool
Encode text to URL-safe percent-encoded format and decode URL-encoded strings — uses encodeURIComponent for safe query parameter encoding.
Frequently Asked Questions
URL Encoding (Percent-Encoding) Explained
URL encoding, formally called percent-encoding (RFC 3986), converts characters that are not safe in URLs into a safe representation. The format is % followed by two uppercase hexadecimal digits representing the character's UTF-8 byte value. A space (byte 0x20) becomes %20, ä (UTF-8: 0xC3 0xA4) becomes %C3%A4.
The unreserved characters (A-Z, a-z, 0-9, -, _, ., ~) never need encoding. Reserved characters (:, /, ?, #, [, ], @, !, $, &, ', (, ), *, +, ,, ;, =) have special meanings in URLs and must be encoded when used as literal data. Non-ASCII characters like emoji must be encoded via their UTF-8 byte sequences.
This tool uses JavaScript's encodeURIComponent(), which is appropriate for encoding query parameter values, form fields, and path components. If you're building a URL from scratch, encode each component separately — never encode the full URL at once or you'll double-encode the structural characters.