JWTs are compact, URL-safe strings used in authorization headers and callbacks. This generator follows the JWS compact form: base64url header, base64url payload and a signature segment separated by dots. Treat it as a local development helper, not a production key-management system.
Free JWT Generator
Runs entirely in your browser - no upload, no sign-up.
Use this for local testing. Do not paste production secrets into tools you do not control.
Generated token
Edit the header and payload to generate a token
What does a JWT generator do?
A JWT generator builds a compact JSON Web Token from a header, payload claims and signing choice. This tool creates HS256 tokens with your browser's Web Crypto API or unsigned tokens for debugging, then shows the copyable three-part token without sending the JSON or secret to a server.
How to use
- 1Edit the header. Keep typ as JWT and choose HS256 or none from the algorithm buttons.
- 2Add payload claims. Write a JSON object with fields such as sub, name, iat, exp or your own custom claims.
- 3Enter a test secret. For HS256, provide a shared secret. Use throwaway development values, not production secrets.
- 4Copy the token. The generator updates after edits and the copy button copies the full compact JWT.
Who it's for
- API prototyping when you need a quick HS256 bearer token for a local mock service.
- Claim debugging when you want to inspect how iat, exp, sub or custom fields change the final token.
- Webhook testing when a sandbox endpoint expects a compact token-shaped value.
- Documentation examples when you need a readable sample JWT with non-sensitive claims.
FAQ
Is the JWT generator free?
Yes. The JWT generator is free to use with no sign-up and no usage limit. It runs in your browser and is meant for development, documentation and testing workflows.
Are my JWT claims or secrets uploaded?
No. The header, payload and HS256 secret are processed in your browser. Still, you should only use throwaway development secrets here, because production token signing belongs in a controlled server or key-management environment.
Does this create production-ready JWTs?
It creates syntactically valid compact JWT strings for local testing. It does not replace your authentication server, key rotation, audience validation, issuer checks, replay controls or secure storage for signing keys.
Which JWT algorithms are supported?
This version supports HS256 using Web Crypto HMAC SHA-256 and the none algorithm for unsigned debugging tokens. It does not handle RS256, ES256 or private-key signing.
What is the none algorithm?
The none algorithm creates an unsigned token with an empty signature segment. Use it only when a test harness explicitly needs an unsigned JWT. Production systems should reject unsigned tokens.
Why did my header alg change?
The selected algorithm button is the source of truth. The generator rewrites the header alg field to HS256 or none so the header matches the signature it actually creates.