inspect header & payload
This tool decodes a JSON Web Token (JWT) and displays its header and payload as readable JSON, letting you inspect the claims inside a token without needing a backend or command-line tool.
Debugging an authentication issue by inspecting a token's claims.
Checking a token's expiry time or issuer during development.
Verifying what data an API is embedding inside a JWT.
No — this tool decodes the header and payload for inspection only; it doesn't verify the cryptographic signature, since that requires the signing secret or public key.
No — decoding happens entirely in your browser; the token is never transmitted anywhere.
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