JWT Signature Verifier & Token Validator
Free in-browser JSON Web Token (JWT) signature verifier and claims validator. Inspect token header, payload claims, verify cryptographic HMAC signatures using your secret key with native Web Crypto API, and check expiration status (EXP/IAT) with zero server data transmissions.
Loading JWT verifier engine...
How to Verify JWT in 3 Steps
Paste JWT Token
Enter your encoded JWT string (header.payload.signature).
Enter Secret Key
Provide the secret key used to sign the token.
Inspect Verification Status
Check signature authenticity and token expiration status instantly.
Frequently Asked Questions
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