JWT Decoder
Decode and inspect JWT tokens online
About JWT Decoder
Decode and inspect JSON Web Tokens (JWT) without any libraries. View the header, payload, and signature of any JWT. Check token claims like expiration (exp), issued at (iat), and custom claims. This tool only decodes — it does not verify signatures. Perfect for debugging authentication flows.
Use Cases
- Debugging OAuth 2.0 and OpenID Connect tokens
- Inspecting token claims and expiration times
- Verifying JWT payload structure during development
- Checking token headers for algorithm information
Frequently Asked Questions
What is a JWT?
A JSON Web Token (JWT) is a compact, URL-safe token format used for securely transmitting information between parties. It consists of three Base64-encoded parts: header, payload, and signature.
Does this verify the signature?
No. This tool decodes and displays the token contents. Signature verification requires the secret key or public key, which should never be shared in a browser tool.
Is it safe to paste my JWT here?
Yes. All decoding happens in your browser. No data is sent to any server. However, never share production tokens with real user data in public forums.