JWT Debugger
Decode JSON Web Tokens (JWT) to view their header and payload. Useful for debugging authentication.
// Header will appear here
// Payload will appear here
About JWT Debugger
The JWT Debugger is a secure tool for decoding and inspecting JSON Web Tokens (JWTs). It allows developers to verify the contents (claims) of a token without validating the signature on the server side.
How to Use?
- Paste your JWT string (usually starting with `eyJ...`) into the input area.
- The tool automatically decodes the header and payload.
- View the decoded JSON data on the right panel.
- Check expiration times and other claims.
Features
- Instant decoding of Header and Payload.
- Human-readable date formatting for `exp`, `iat`, and `nbf` claims.
- Syntax highlighting for JSON structure.
- Works entirely client-side (your tokens are not sent to any server).
FAQ
What is a JWT?
JSON Web Token (JWT) is an open standard (RFC 7519) that defines a compact and self-contained way for securely transmitting information between parties as a JSON object.
Is it safe to paste my token here?
Yes. This tool runs 100% in your browser using JavaScript. Your tokens are never transmitted to our servers or any third party.
Can I edit the token?
You can decode it to read the contents, but you cannot edit and re-sign a token without the original secret key. Modifying the token invalidates its signature.
What are common claims?
Common claims include `sub` (subject), `iss` (issuer), `exp` (expiration time), and `iat` (issued at). Custom claims can also be included.