Free Developer Tool

JWT Decoder & Verifier

Decode any JWT's header and payload, get its registered claims explained in plain English, see expiry status and an alg:none security warning, and verify HMAC or RSA signatures — entirely in your browser, safe to paste real tokens.

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Tool

Paste a JWT above (or load the example) to decode its header, payload, and verify its signature.

Everything — decoding and signature verification — runs entirely in your browser via the Web Crypto API. Nothing is ever sent to a server, so it's safe to paste real tokens.

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FAQ

Frequently Asked Questions

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