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Encoders

URL Encoder / Decoder

Percent-encode text for safe use in URLs, decode percent-encoded strings, or parse a full URL to inspect its components and query parameters.

How it works

URLs may only contain a specific set of ASCII characters. Any character outside that set must be percent-encoded: replaced with a % followed by its two-digit hexadecimal byte value. For example, a space becomes %20.

This tool uses encodeURIComponent and decodeURIComponent for component encoding, and the browser's URL API for full URL parsing.

Common uses

  • Query string values — encode user input before appending to a URL: ?q=hello+world
  • Redirect URLs — encode the destination URL when passing it as a query parameter
  • API debugging — decode a URL from a log or curl command to see the original parameters
  • OAuth callbacks — decode the redirect_uri and state parameters from OAuth flows

🔒 Privacy

All URL encoding and parsing happens in your browser. Your input is never sent to any server.

Edge cases and limits

  • Space: %20 vs + — encodeURIComponent uses %20. Form-encoded bodies use + for spaces. The tool uses %20.
  • Invalid percent sequences — a % not followed by two hex digits (e.g. %ZZ) is invalid and will show an error in decode mode.
  • Repeated parameters — ?a=1&a=2 is valid and shows both values in the parse table.
  • Missing protocol — the URL parser requires a protocol (https://). Without it, the URL is treated as a relative path.
  • Unicode — multi-byte characters are UTF-8 encoded before percent-encoding.

FAQ

What is the difference between URL encoding and Base64?

URL encoding escapes characters that are unsafe in URL contexts using %XX hex sequences. Base64 encodes arbitrary binary data as alphanumeric characters. They solve different problems: URL encoding preserves readability for text, Base64 is for binary-to-text conversion.

Should I encode the full URL or just the parameter values?

Encode individual values before inserting them into a URL (use encode component mode). Encoding a complete URL encodes the protocol and slashes, breaking it. Most programming languages provide separate functions for each: encodeURI vs encodeURIComponent in JavaScript.

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