A JSON Web Token (JWT) is a compact, URL-safe token format used for securely transmitting information between parties. It consists of three parts: header, payload, and signature.

Does this tool verify the signature?

No, this tool only decodes and displays the JWT contents. Signature verification requires the secret key or public key, which should never be shared in a browser tool.

Is it safe to paste my JWT here?

Yes! All decoding happens in your browser. Your token is never sent to any server. However, avoid sharing JWTs publicly as they may contain sensitive information.

What do the timestamps mean?

Common JWT timestamp fields: 'iat' (issued at), 'exp' (expiration time), 'nbf' (not before). These are Unix timestamps (seconds since Jan 1, 1970). The tool shows the human-readable date next to each.

JWT Decoder

Your files never leave your device

Decode and inspect JSON Web Tokens. View the header, payload, and signature. Check token expiry. All processing happens in your browser — your tokens never leave your device.