🧰 HeavyToolz
🪪

JWT Decoder

Decode a JSON Web Token's header and payload to inspect its claims — no signature verification.

Frequently asked questions

Does this verify the token's signature?

No, this only decodes the header and payload for inspection. It doesn't verify the signature, since that would require the signing secret or key.

Is my token sent anywhere?

No, decoding happens entirely in your browser using standard Base64URL decoding — the token never leaves your device.

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