JWT decoder online
Free online JWT decoder. Decode JWT tokens, view header, payload and signature with real-time expiration check.
How it works
- 1
Paste the JWT token
Copy the complete JWT token (3 parts separated by dots: header.payload.signature) and paste it into the input field.
- 2
View the 3 decoded sections
The decoder automatically shows Header (algorithm and type), Payload (data and dates) and Signature in readable JSON format.
- 3
Check temporal validity
A visual indicator shows whether the token is still valid or expired, based on the exp and nbf fields in the Payload.
FAQ
What is a JWT?
JWT (JSON Web Token) is a standard for securely transmitting information between parties. It consists of 3 parts separated by dots: header.payload.signature.
Does the decoder verify the signature?
No, the decoder only shows the token content. Signature verification requires the secret key that only the server possesses.
Is the token sent to a server?
No, decoding happens entirely in the browser using atob() for Base64. No data leaves your device.
