Encode or decode URLs and query strings instantly, with automatic parsing of paths, parameters, and percent-encoded special characters.
| Key | Value | Actions |
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No query parameters. Use "Add Param" to build one.
Access recent query strings or URLs copied during this session.
URLs can only safely contain a limited set of characters. Special symbols, spaces, emojis, and non-English characters must be converted into a standardized format so browsers and servers can correctly interpret and transmit the information.
URL encoding replaces unsupported or reserved characters with hexadecimal values prefixed by a percent sign (%). This ensures query parameters, file names, and user-generated content can travel through URLs without breaking their structure.
encodeURI() is designed for complete URLs and preserves structural characters such as slashes and question marks. encodeURIComponent() is intended for individual parameter values. Strict RFC 3986 encoding additionally escapes the sub-delimiters !'()* that JavaScript leaves untouched by default, which matters for some strict API providers.
HTML forms submitted as application/x-www-form-urlencoded encode spaces as + rather than %20. Use the Form mode when building or debugging query strings that originate from HTML form submissions.
URL encoding only converts characters into a transport-safe format. It does not hide, protect, or secure information. Anyone can decode encoded values, so sensitive data should never be exposed in URLs without proper encryption and security controls.
Quick answers about how this tool works.
encodeURI() is designed to encode a complete, functional URL (it keeps special URL syntax characters like "/", "?", "#", "@", and "&" unescaped). encodeURIComponent() is designed to encode individual URL components or query parameter values (it escapes all special syntax characters, ensuring they do not interfere with the structure of the host URL).
URLs are transmitted over the internet using the US-ASCII character set. Characters outside this set (such as emojis or non-English letters) or characters that have reserved structural meanings in URLs (like spaces, "?", and "=") must be encoded to prevent protocol parsing errors and transport corruption.
It converts characters to their UTF-8 byte sequence representation and then represents each byte value as a hexadecimal pair prefixed by a percent symbol (%). For example, a space character (Unicode U+0020) maps to %20, and the fire emoji 🔥 maps to %F0%9F%94%A5.
In query strings, spaces are historically encoded as plus symbols (+) according to the application/x-www-form-urlencoded standard. This tool automatically provides options to translate "+" into literal spaces when decoding query parameter blocks.
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