DeveloperRuns locally · No upload

JWT Generator

Build JSON Web Token headers and payloads, then sign them with HMAC (HS256/384/512) for development and testing. Same workbench as the JWT Decoder — switch tabs to decode, verify, or sign.

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

Is the generated JWT signed?+

Yes, when you provide a secret on the Sign tab. The token is signed with the algorithm in the header (HS256, HS384, or HS512). Use the Verify tab to confirm the signature.

Is it safe for production tokens?+

This tool is for debugging and learning. Production tokens should always be signed on your server with secrets that never leave your backend.

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.