URL Encoder & Decoder

URL encoding (also known as percent-encoding) is a mechanism to translate arbitrary characters into a safe format that can be transmitted over the Internet within Uniform Resource Identifiers (URIs). It replaces characters not allowed in URLs with a '%' symbol followed by the character's two-digit hexadecimal ASCII/UTF-8 representation (e.g., a space becomes '%20').

URLs are limited to a small subset of the US-ASCII character set (alphanumeric characters and a few safe symbols). Characters outside this set (such as spaces, emojis, non-English alphabets) or characters with special syntactic meanings in URLs (like '?', '&', '=', '/', and '#') must be encoded when they are included as text content within query parameters, path variables, or header tokens to prevent parsing errors.

encodeURI is designed to encode a complete, valid URL. It preserves URL syntax characters such as 'http://', '/', '?', '&', '=', and '#' so the URL remains functional. encodeURIComponent is designed to encode individual URL segments (such as query parameters or path variables). It encodes syntax characters as well, turning '/' into '%2F' and '&' into '%26', to prevent them from interfering with the parent URL structure.

Under RFC 3986, characters are split into: Unreserved (which never need encoding, including letters, numbers, hyphen, underscore, period, and tilde) and Reserved (which have special meanings in some URL contexts, such as ':', '/', '?', '#', '[', ']', '@', '!', '$', '&', '*', '+', ',', ';', '='). If a reserved character is used as literal text inside a query parameter, it must be encoded; otherwise, it is treated as a URL separator.

Yes, completely. Our encoder and decoder utilize UTF-8 multi-byte encoding. When you enter Unicode text (like emojis or Japanese/Arabic characters), the tool translates each character to its corresponding UTF-8 byte sequence and percent-encodes each byte (e.g., '👋' is encoded as '%F0%9F%91%8B'). This ensures accurate, lossless text translation across all systems.

No. ToolZeno operates 100% client-side. All URL encoding, decoding, validation, and statistics generation are executed inside your browser using JavaScript. No information is transmitted to our servers. This ensures complete privacy for sensitive API endpoints, query strings, and system payloads.