absurdtools

JWT Decoder

Decode a JSON Web Token to inspect its header and payload.

🔒 Signature is not verified — decoding only reveals the contents. Never paste production secrets.

How to use

  1. Paste your JWT.
  2. See the decoded header and payload as formatted JSON.
  3. Review standard claims such as expiry and issuer.

Frequently asked questions

Does it verify the signature?

No. Decoding shows the token contents but does not validate the signature, which requires the secret or key. Never paste production secrets anywhere.

Is it safe to paste a token here?

Decoding happens entirely in your browser and nothing is sent anywhere, but avoid pasting sensitive production tokens as a general habit.

🔒 This tool runs entirely in your browser. Nothing you enter is uploaded, logged, or stored.

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