Developer tool
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This tool encodes the string you paste as a single component — the way you would encode one query value or path segment. It is not encodeURI, which leaves certain reserved characters alone for full URL strings. If your job is fix hello world in a parameter, you are in the right place; if you need to encode an entire URL with slashes intact, use encodeURI semantics elsewhere.
The strings people encode are often half-built auth redirects, signed callback URLs, or internal service names. Pasting them into a server-side encoder adds another system that saw the value. Here the transformation runs in the page only.
No Punycode for internationalised domain names, no HTML form application/x-www-form-urlencoded rules where spaces become +, and no automatic parsing of a full URL into parts. decodeURIComponent will throw on malformed sequences — that is expected.
That is the promise behind every tool here. Files are read in your browser tab, processed there, and discarded when you close it — never uploaded to our servers.
Encode to Base64 or decode from Base64 instantly in your browser.
Decode JSON Web Tokens (JWT) safely to view header and payload without sending secrets to any server.
Format, validate, prettify and beautify your JSON data instantly.
MD5 for checksums plus SHA-1, SHA-256, and SHA-512 via Web Crypto — all in your browser, nothing uploaded.
Test, visualize, and debug Regular Expressions instantly in your browser.
Format and beautify your messy HTML code instantly in your browser.
