DeveloperRuns locally · No upload

JWT Decoder Online Free

Paste a JSON Web Token to inspect header and payload claims, check expiration at a glance, and verify HMAC or RSA signatures — decode, verify, and sign test tokens in one workbench without sending tokens to a server.

Utiliio vs JWT.io — Decode, Verify & Sign Tokens Privately
Private by design

Everything runs in your browser. Your input is never uploaded, stored, or logged on our servers.

Works offline after load

Frequently asked questions

How do I decode a JWT online for free?+

Paste the token into the Decode tab — header and payload appear as formatted JSON instantly with a claims table and expiry badge.

Can this tool verify JWT signatures?+

Yes. Open the Verify tab. For HS256/384/512, paste the HMAC secret. For RS256/384/512, paste the PEM public key (SPKI format). Verification runs locally via Web Crypto.

Does this tool sign JWTs?+

Yes. Use the Sign tab to build and sign test tokens with HS256, HS384, or HS512. For production auth, always sign tokens on your server.

Is this tool free?+

Yes. Every Utiliio utility is free with no sign-up, usage limits, or paywalls.

Do you store my data?+

No. Processing happens entirely in your browser. Your input never leaves your device.

Can I use this tool offline?+

Yes. Once the page loads, most tools continue working without an internet connection.