JWT Debugger
Decode and debug your JSON Web Tokens instantly.
Client-side only. Your tokens never leave your browser.
How to Debug JWTs?
JSON Web Tokens (JWT) are widely used for authentication. This debugger allows you to:
- Inspect Claims: See exactly what data is inside the token (User ID, Expiry, Roles).
- Verify Structure: Check if the token has the correct Header, Payload, and Signature structure.
- Debug Expiration: Check the `exp` claim to see if your token is expired.
Note: We do not verify the signature because that requires your secret key, which should never be shared.
Secure Offline JWT Debugger
JWT (JSON Web Token) is the open standard for secure information exchange. UnitMaster's debugger allows you to paste and inspect tokens instantly without them ever leaving your browser. A 'Must-Have' for privacy-conscious developers.
100% Client-Side
Your tokens never touch our server. This is critical for security, as you should never paste real JWTs into online tools that send data to a backend.
Header / Payload / Signature
We automatically split and color-code the token into its three core components for easy debugging.
Expiration Parsing
Instantly see when a token expires (exp) or was issued (iat) in a human-readable date format.
Why choose UnitMaster?
- Debug authentication issues.
- Verify token claims.
- Check expiration dates.
- Securely inspect production tokens.