JWT Decoder & Security Inspector

What Is a JWT Decoder?

JWT (JSON Web Token) is a compact, URL-safe way of representing claims between two parties. JWTs are often used for authentication in web apps. This JWT decoder helps you view the contents of any JWT, separating its header, payload, and signature.

Why Check JWT Security?

• 🔍 Ensure the token is not using insecure algorithms like none
• ⏱ Verify if the token is expired (via the exp claim)
• 🔐 Check claim integrity and structure before trusting a JWT

How to Use:

1. Paste your JWT token into the textarea above.
2. Click “Decode JWT” to see the decoded header, payload, and signature.
3. Review security tips automatically shown based on token content.

This tool does not validate signatures and is for educational/debugging use. Do not paste production secrets.

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