JWT Debugger

Decode and inspect JSON Web Tokens instantly. Verify payloads and headers securely in your browser without exposing your tokens to third-party servers.

Header will appear here
Payload will appear here

What is a JWT Decoder?

A JWT (JSON Web Token) Decoder is an essential security and debugging tool that unpacks the encrypted or Base64-encoded payload of a JSON Web Token. It allows developers to inspect the token's header, claims (like user ID and expiration), and verify its signature.

How do JSON Web Tokens work?

JWTs are widely used in modern authentication systems (like OAuth 2.0 and OpenID Connect). A token consists of three parts separated by dots: a Header (containing the algorithm), a Payload (containing the claims), and a Signature (used to verify the token hasn't been tampered with).

Why use our JWT Debugger?

Tokens often contain highly sensitive user data and authentication credentials. Sending your live JWTs to random online decoders is a massive security risk. DevvTools parses and decodes your tokens 100% locally in your browser. Your tokens never leave your device, ensuring complete privacy and security while you debug your authentication flows.