JWT Decoder
Decode a JSON Web Token to inspect its header and payload. Decoding only — no verification, all in your browser.
Runs in your browser — files never leave your device
This decodes the token only — it does not verify the signature.
How it works
Paste a JWT to see its decoded header and payload as formatted JSON.
Useful for debugging auth flows and inspecting claims like exp and iat.
Frequently asked questions
- Does this verify the signature?
- No — it only decodes the header and payload so you can inspect the claims. Verification needs the secret/key.
- Is my token uploaded?
- No — decoding happens entirely in your browser. Still, avoid pasting production tokens you consider secret.
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