🎫 JWT Generator offline
Free offline JWT generator. Generate fake JWT tokens for testing in your browser.
About JWT Generator
JWT Generator creates test JWT tokens with custom headers and payloads. Use these tokens for development and testing purposes only. This tool does NOT produce cryptographically secure signatures.
Features
- ✓Generate JWT tokens with custom data
- ✓Pre-built templates for common use cases
- ✓Customize header and payload JSON
- ✓Set custom secret key
- ✓Copy generated token instantly
- ✓Works offline in your browser
How to Use
- 1.Choose a template or customize header/payload
- 2.Enter your secret key
- 3.Click "Generate JWT Token"
- 4.Use the token for testing (not production!)
⚠️ Warning
For testing only! This tool generates tokens with a simplified signature algorithm that is NOT cryptographically secure.
Never use these tokens in production. For real JWT generation, use proper libraries like jsonwebtoken (Node.js), PyJWT (Python), or similar server-side libraries.
How to Use
Pick a template, edit the header and payload JSON, enter a secret key, and click Generate. The token is built locally, so you can safely test auth flows without sending claims anywhere. I use this when I need predictable tokens while building UI states or API mocks.
Example payload
{"sub":"user_123","role":"admin","exp":1700000000}- Select a template or paste custom JSON.
- Update claims like
sub,role, andexp. - Enter a secret key for the test signature.
- Click Generate and copy the token.
Use Cases
Typical times I generate test JWTs:
- Frontend development without a live auth backend.
- API testing in Postman or Insomnia with realistic claims.
- Prototyping different user roles and permissions.
- Learning JWT structure by experimenting with claims.
Tips & Best Practices
Use realistic claims
Include exp, aud, and roles so your client behaves like production.
Remember these are not secure
The signature here is simplified. Use real libraries on the server for production tokens.
Keep secrets out of source control
Even test secrets shouldn’t live in repos. Treat them like real credentials.
Verify on the backend
Even in tests, keep verification logic server-side to mirror production behavior.
Comparison with online tools
Online generators can expose claims and secrets. TurboUtil keeps your test payloads local and avoids accidental data leaks.
Online generators
- Upload payloads to third-party servers
- Potential logging or retention
- Require internet connection
- Not ideal for sensitive data
TurboUtil
- All token generation is local
- No uploads or tracking
- Works offline after load
- Instant output for testing
FAQ
Are these tokens production-ready?
No. The signature is simplified. Use server-side libraries for real JWTs.
Can I set custom claims?
Yes. Edit the payload JSON to include any custom fields you need.
Is my data uploaded?
No. Everything runs locally in your browser.
Why does the signature not match my backend?
This tool does not implement full cryptographic signing. It is for testing only.