JWT Verifier

Verify JWT tokens instantly with our free online tool. Check signature validity and view decoded data with syntax highlighting. No installation required.

JWT Token

Secret Key

Header

Payload


Our JWT verifier helps you validate JWT tokens by checking their signatures and decoding their contents. Perfect for testing authentication tokens or debugging JWT issues. The verification happens entirely in your browser, ensuring your tokens stay private and secure.

Frequently Asked Questions

How do I verify a JWT token?
Paste your JWT token, enter the secret key or public key used for signing, and the tool will verify the signature and show you the token's contents.
What does JWT verification check?
Verification checks the token's signature validity, ensures it hasn't been tampered with, and validates any expiration (exp) or not-before (nbf) claims if present.
Why might a JWT verification fail?
Common reasons include invalid signatures, expired tokens, incorrect secret keys, or tokens that aren't yet valid (based on nbf claim).
Can I verify tokens signed with different algorithms?
Yes, the tool supports verification of tokens signed with HMAC (HS256, HS384, HS512) and RSA (RS256, RS384, RS512) algorithms.
Is the verification process secure?
Yes, all verification is done locally in your browser. Your keys and tokens never leave your device.