Decode and inspect JSON Web Tokens (JWT) in real-time. Verify structures and examine token expiration details securely inside your browser.
📋 HEADER: ALGORITHM & TOKEN TYPE
{ }
📄 PAYLOAD: DATA & CLAIMS
{ }
🔒 SIGNATURE: VERIFIED (CLIENT SIDE)
HMACSHA256( ... )
How JWT Decoder works
Input or paste your encoded base64 JSON Web Token (JWT) into the **Encoded** textarea.
JWT tokens are composed of three parts separated by dots (`.`): Header, Payload, and Signature.
The decoder splits the segments, performs Base64Url decoding, and formats JSON claims instantly in your browser.
**100% Secure**: Decoding is completed entirely client-side using JavaScript. Your tokens never leave your computer, ensuring database keys or sub IDs are kept private.