Are my files uploaded to a server?

No. This tool runs entirely in your browser using JavaScript — your files never leave your device.

Does it verify the signature?

No — it decodes and displays the token. Signature verification requires the secret/public key and should be done server-side.

Decoding happens locally in your browser and the token is never transmitted. Still, avoid sharing production tokens anywhere.

Decode JSON Web Tokens online for free. Inspect header, payload and expiry instantly — the token never leaves your browser.

Paste JWT

Are my files uploaded to a server?: No. This tool runs entirely in your browser using JavaScript — your files never leave your device.
Does it verify the signature?: No — it decodes and displays the token. Signature verification requires the secret/public key and should be done server-side.
Is it safe to paste a real token?: Decoding happens locally in your browser and the token is never transmitted. Still, avoid sharing production tokens anywhere.