URL encoding is required whenever special characters appear in query strings, form data, or REST API paths. A misplaced unencoded & or + can silently corrupt a parameter value. This tool encodes and decodes individual strings and parses complete URLs into their RFC 3986 components — useful for debugging OAuth redirect URIs, webhook endpoints, and query parameter issues.
Encoding uses the browser-native encodeURIComponent() function, which implements RFC 3986 unreserved character set encoding. Decoding uses decodeURIComponent() with a try/catch that falls back to a manual byte-level decode for malformed or Latin-1-encoded sequences.
URL parsing uses the browser-native URL constructor, which implements the WHATWG URL standard. It reliably handles edge cases like missing protocols, IPv6 hosts, and IDN (internationalised domain names). Query parameters are extracted via URLSearchParams, which correctly handles repeated keys and plus-sign space encoding.
A developer debugging a broken OAuth redirect URL encodes the callback URL before adding it as a query parameter, then verifies the round-trip decode is lossless.
A backend engineer parses an incoming webhook URL to extract query parameters and confirm the signature matches without writing a one-off Node.js script.
A QA tester decodes a percent-encoded error message embedded in a redirect URL to read the original error text from the server.
Paste a URL or string into the input field
Toggle between Encode and Decode to convert the string
Switch to URL Parser mode to break a full URL into components
Copy individual components or the full result with the copy buttons
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