100% Client-Side Privacy

JWT Token Decoder & Inspector

Decode JSON Web Tokens locally in your browser to inspect headers, payload claims, and expiration.

Encoded JWT Token

Header: Algorithm & Token Type

Payload: Data Claims

Secure & Fast Online JWT Token Inspector

JSON Web Tokens (JWT) are widely used for authenticating user sessions in modern REST APIs and OAuth applications. OptMyTool's JWT Decoder lets developers instantly decode and inspect JWT header algorithms, claims, user roles, and expiration dates directly in the browser.

🔒 Zero Server Exposure

Unlike online tools that route your tokens through backend APIs, OptMyTool decodes your JWT strings locally in browser memory using native Base64 URL decoding.

⏰ Real-time Expiration Detection

Automatically calculates UNIX `exp` timestamp claim against system time to display whether your JWT is currently valid or expired.

100% client-side processing. Your data never leaves your browser.