JWT Signer

Sign JWT tokens instantly with our free online tool. Customize header and payload with syntax highlighting and validation. No installation required.

Header

Payload

Secret Key

JWT Output


Our JWT signer helps you create JWT tokens by signing your custom headers and payloads. Perfect for testing authentication systems or generating tokens for development. The signing happens entirely in your browser, ensuring your data stays private and secure.

Frequently Asked Questions

What is a JWT token?
A JSON Web Token (JWT) is a compact, URL-safe means of representing claims between two parties. It's commonly used for authentication and information exchange.
How do I create a JWT token?
Enter your payload data in JSON format, select your preferred signing algorithm, provide a secret key, and click 'Sign'. The tool will generate a signed JWT token instantly.
What algorithms are supported?
We support common JWT signing algorithms including HS256, HS384, and HS512 for HMAC-based signatures, and RS256, RS384, and RS512 for RSA-based signatures.
Is my data secure when using this tool?
Yes, all JWT operations are performed locally in your browser. Your keys and data never leave your device.
What claims should I include in my JWT?
Common claims include 'sub' (subject), 'iat' (issued at), 'exp' (expiration), and 'iss' (issuer). You can add any custom claims as needed for your application.