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JWT Generator

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

Base64 EncoderJWT DebuggerHash Generator (Bcrypt/SHA)
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.
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JWT Generator

When building or testing authentication systems, you often need JWT tokens with specific claims for testing. Creating these tokens manually — encoding the header, encoding the payload, computing the HMAC signature — is tedious and error-prone.

This JWT generator lets you edit the header and payload as JSON, provide a secret key, and generates a properly signed JWT using the browser's native Web Crypto API for HMAC-SHA256 signing. The entire process — JSON encoding, Base64URL encoding, and cryptographic signing — happens locally in your browser.

This is especially important for security-sensitive work. Many online JWT generators transmit your secret key and payload to a server for processing, which completely defeats the purpose of using signed tokens. This tool keeps your signing keys private.

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.

JWT Generator Examples

Before 
Header: {"alg":"HS256","typ":"JWT"}
Payload: {"sub":"user-123","role":"admin"}
After 
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VyLTEyMyIsInJvbGUiOiJhZG1pbiJ9.signature

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.

Related Tools

Base64 EncoderJWT DebuggerHash Generator (Bcrypt/SHA)