Percent-Encoding Reference Table
Searchable RFC 3986 reference: every ASCII character with its %XX code, reserved/unreserved class and where it must be escaped.
About Percent-Encoding Reference Table
Percent-Encoding Reference Table is a searchable RFC 3986 chart of every ASCII character with its %XX code and its reserved / unreserved class — so you can see at a glance which characters must be escaped in a URL and which are safe to leave alone.
How to use Percent-Encoding Reference Table
- 1Paste or type your input into the box above — a sample is pre-filled so you can try it instantly.
- 2Set any options on offer (mode, key, format) to match what you need.
- 3The result appears the moment you type — no button to press, no waiting.
- 4Click Copy to grab the output — Percent-Encoding Reference Table keeps everything on your device.
Why use Percent-Encoding Reference Table?
- ✓Deciding whether a character in a path or query value needs escaping
- ✓Looking up a %XX code you found in a log or a malformed URL
- ✓Teaching or revising the reserved vs unreserved character rules
- ✓100% free with no sign-up, no watermark and no usage limits
- ✓Runs entirely in your browser — your text and keys are never uploaded, stored or logged
- ✓Works offline once loaded, with instant results and one-click copy
Frequently asked questions
Which characters must be percent-encoded in a URL?+
Anything that is not unreserved (letters, digits and - . _ ~) should be encoded when it appears inside data. Reserved characters (: / ? # [ ] @ ! $ & ' ( ) * + , ; =) carry URL structure and are only encoded when used literally.
What is %20 versus +?+
%20 is the percent-encoding of a space and is valid everywhere in a URL. The + sign also means space, but only inside application/x-www-form-urlencoded query strings — not in paths.
Is it free to use?+
Yes — completely free with no sign-up, no account and no usage limits. There is no paywall, so you can encode, decode and convert as much as you like.
Is my data private and secure?+
Yes. This tool runs entirely in your browser using client-side JavaScript — your input is never uploaded to a server, stored or logged. Once the page has loaded you can use it offline, which makes it safe for tokens, keys and confidential data.
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