Easily encode and decode URL strings, query parameters, path components, and OAuth redirect URIs using standards-compliant percent-encoding.
All formatting, parsing, decoding, and validation executes entirely within your browser using modern Web APIs and JavaScript. Your tokens, JSON payloads, regex inputs, and queries never leave your computer.
URLs can only be sent over the Internet using the ASCII character-set. When URLs contain non-ASCII characters or reserved characters like ?, &, =, #, or spaces, they must be converted into valid ASCII using percent-encoding (% followed by two hexadecimal digits).
DevRef's Online URL Tool supports both component-level encoding (encodeURIComponent for query string values) and full URL encoding (encodeURI for complete links). It instantly highlights decoding errors, handles multi-byte UTF-8 character sequences, and runs 100% locally in your browser so private tokens, authentication parameters, and session URLs remain strictly confidential.
encodeURI is meant for complete URLs; it preserves reserved protocol and structural characters such as ://, ?, &, and =. encodeURIComponent is designed for individual parameter values, encoding characters like & and = so they are not misinterpreted as query delimiters.
RFC 3986 specifies %20 as standard percent-encoding for spaces across all URL parts. The plus sign (+) is traditionally used in application/x-www-form-urlencoded query strings, but %20 is universal and safer across modern REST APIs.
No. All encoding and decoding runs in your browser's local JavaScript environment. No query strings, tokens, or URLs are logged or sent to any server.
Practical examples and pitfalls when constructing REST API queries and OAuth redirect URLs.
Understand Content-Type, Authorization, and Cache-Control headers in HTTP communications.
Encode binary data or authentication strings for HTTP headers and Basic Auth.