Security ToolsPrivate by design
JWT Signature Verifier (HS256)
Enter a JWT and its secret to verify the signature is valid, computed entirely in your browser.
How to use this tool
- 1Paste the JWT.
- 2Enter the secret key.
- 3See whether the signature is valid, and the decoded payload.
Frequently asked questions
Does this support RS256 tokens?+
No — this only verifies HS256 (shared-secret) tokens. RS256/ES256 use asymmetric key pairs, a different verification process this tool doesn't implement.
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