How do I decode a URL-encoded string?

Select 'Decode' mode and paste — malformed input (a % not followed by two hex digits) will be flagged.

Why does %20 keep appearing as %2520?

That's double encoding — something encoded an already-encoded string. %2520 is literally the percent-escape of the text '%20'. Decode twice, or fix the source to encode once.

What's the difference between a URL and URI?

A URL is a URI that also tells you how to locate the resource (scheme + host). In daily work the terms are interchangeable; the standard that governs parsing is WHATWG URL.

Why does analyze fail on 'example.com'?

A URL needs a scheme — the parser can't guess it's a URL without 'https://'. Add the scheme, or use encode mode.

URL Encoder, Decoder & Analyzer — Parse Any URL

Percent-encode or decode strings, and break any URL into protocol, host, path, query params and fragment — decoded params listed cleanly.

ModeURL or stringEverything runs locally in your browser — pasted content is never uploaded, logged or stored.

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Last reviewed 2026-10-19. Rates change — verify against the official sources linked below before relying on these figures.

What this is based on

Analyze mode parses via the WHATWG URL parser (same as your browser's new URL()).
Encode uses encodeURIComponent — safe for query values, encodes reserved characters like / : ? & =.
Everything runs locally in your browser — pasted content is never uploaded, logged or stored.

WHATWG URL Standard ↗

encodeURIComponent vs encodeURI — the classic bug

encodeURIComponent escapes everything that could confuse a query string (including & = ? /), while encodeURI preserves URL structure characters. Pick wrong and your redirect breaks: a callback URL passed as a ?redirect= parameter MUST use encodeURIComponent, or the inner '?' and '&' leak into the outer query.

Rule of thumb: encodeURIComponent for any value going INSIDE a URL; encodeURI only for whole-URL display encoding.

What percent-encoding actually does

URLs can only carry a limited ASCII set. Everything else — spaces, non-English characters, and characters with special meaning — gets percent-encoded: each byte becomes % followed by its hex value. ' ' → %20, 'ć' → %C4%87 (two UTF-8 bytes). Double-encoding is the classic bug: encode once, and %20 becomes %2520.

Frequently asked questions

How do I decode a URL-encoded string?: Select 'Decode' mode and paste — malformed input (a % not followed by two hex digits) will be flagged.
Why does %20 keep appearing as %2520?: That's double encoding — something encoded an already-encoded string. %2520 is literally the percent-escape of the text '%20'. Decode twice, or fix the source to encode once.
What's the difference between a URL and URI?: A URL is a URI that also tells you how to locate the resource (scheme + host). In daily work the terms are interchangeable; the standard that governs parsing is WHATWG URL.
Why does analyze fail on 'example.com'?: A URL needs a scheme — the parser can't guess it's a URL without 'https://'. Add the scheme, or use encode mode.

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