JWT Debugger
Decode JWTs and verify their signatures.
Runs in your browser: what you paste is never uploaded
How to use JWT Debugger
- 1Paste or type your inputUse the box above, or click Sample to try it with an example.
- 2Choose your optionsPaste the token; add the secret (HS256/384/512) or public key (RS, PS or ES algorithms) to verify it.
- 3Copy the resultCopy it with one click. Nothing is sent anywhere.
About JWT Debugger
Decode JSON Web Tokens to read their header and claims, check expiry, and verify the signature with a secret or public key.
Frequently asked questions
Is it safe to paste a real token?
Yes. Decoding and verification happen in your browser with WebCrypto; the token and keys are never sent anywhere.
Does decoding mean the token is valid?
No. Anyone can decode a JWT. Only a verified signature shows it was issued by the key holder and not altered.
Is what I paste sent anywhere?
No. The tool runs entirely in your browser and never sends what you type or paste to a server.
Is it free?
Yes. It's free, with no sign-up and no limits.
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