JWT Debugger & Generator — Secure & Instant

What is a JWT?

A JSON Web Token (JWT) is a compact and self-contained way to represent claims between two parties. It's primarily used for authentication and authorization in web applications. JWTs are signed to ensure the data is tamper-proof.

Structure of a JWT

How JWT Debugging Works

• Paste a JWT token to auto-decode its Header and Payload
• Edit either the token or the JSON to reflect changes on the other side
• Verify the signature using a known secret key (for HS256)
• Create your own JWT by editing Header + Payload + Secret
• Copy outputs or test in real authentication flows

Common JWT Claims

Why Use This JWT Tool?

• ✅ Everything runs locally in your browser — safe and fast
• 🛠 Edit and verify JWTs for real-world use cases
• 🔐 Validate HS256 signatures instantly
• 🔄 Bidirectional sync between token & JSON editor
• 🧠 Great for learning, development, or debugging auth systems

Example JWT

Header:

{
  "alg": "HS256",
  "typ": "JWT"
}

Payload:

{
  "user": "zonayed",
  "role": "admin",
  "iat": 1698000000,
  "exp": 1700692000
}

Secret: my-secret-key

Developer Use Cases

• 🧪 Test and debug your authentication flow
• 🎓 Learn how JWTs work in real-time
• 🛡 Ensure signature validation with test secrets
• 🔧 Build mock tokens for backend/frontend testing