Is my secret key safe?

Yes, signature verification happens locally in your browser. Your secret key is never sent to any server.

JWT Debugger

Free online JWT Debugger. Decode JSON Web Tokens (JWT) to view header and payload. Verify signatures with your secret key. Supports HS256.

100% PrivateInstant ProcessingNo Upload Required

Free online jwt debugger tool. Process your files securely in your browser - your data never leaves your device.

Encoded Token

HeaderAlgorithm & Token Type

PayloadData Claims

Your-256-bit-secret

Note: Only HS256 (HMAC with SHA-256) verification is supported in the browser client-side debugger currently.

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