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JWT Generator

Create test JWT tokens with custom headers and payloads locally. Sign with HMAC-SHA256 using Web Crypto API.

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JWT Generator
Create test JWT tokens locally. Sign with HMAC-SHA256 using Web Crypto API.
Ctrl+Enter Generate Web Crypto API
Header (JSON)Editable
Payload (JSON)Editable
Generated JWTRead only
ReadyBrowser only
Edit the header and payload, then click Generate to create a signed JWT.

How ZeroData protects your privacy

  • ✓ No Uploads: Processing happens entirely via client-side JavaScript.
  • ✓ No Storage: We do not have a database. We physically cannot save your data.
  • ✓ No Tracking: We don't log what you process or track your inputs.
  • ✓ Verifiable: Check your DevTools Network tab. You will see 0 outbound requests.

How to Use the JWT Generator

  1. Edit the header JSON (algorithm and type are pre-filled).
  2. Edit the payload JSON with your desired claims (sub, name, exp, etc.).
  3. Enter your HMAC secret key in the secret field.
  4. Click Generate to create a properly signed JWT token.
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Frequently Asked Questions

Is my secret key sent to a server?

No. HMAC-SHA256 signing is performed entirely in your browser using the Web Crypto API. Your secret key never leaves your device.

What signing algorithms are supported?

Currently, this tool supports HMAC-SHA256 (HS256), which is the most widely used JWT signing algorithm.

Can I use this JWT in production?

The generated token is a valid, properly signed JWT. However, we recommend using this for testing and development only. Production tokens should be generated by your application's authentication system.

Does this complement the JWT Debugger?

Yes. You can generate a JWT here and decode it with our JWT Debugger to verify the claims are correct.

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