JWT Decoder
NewDecode JSON Web Tokens (JWT) instantly to inspect their header, payload, and signature. See the algorithm used, expiration time, issued-at time, and all claims stored in the token. Useful for debugging authentication flows, inspecting tokens during development, and understanding JWT structure. All decoding happens in your browser — your tokens are never sent to any server.
JWT Decoder
Decode and inspect JSON Web Tokens instantly. Tokens stay in your browser.
How to Use JWT Decoder
- 1Paste your JWT token into the input field
- 2The header and payload are decoded and displayed immediately
- 3Inspect the claims, expiration time, and algorithm
- 4Note: Signature verification requires the secret key
Your Privacy is Protected
JWT Decoder runs entirely in your browser. Your files and data are never uploaded to any server, never stored, and never shared. Everything happens locally on your device using secure browser APIs.
Frequently Asked Questions
What is a JWT?
A JSON Web Token (JWT) is a compact, URL-safe token format used to transmit claims between parties. It contains a header, payload, and signature, each encoded in Base64.
Can this tool verify JWT signatures?
This tool decodes the header and payload. Full signature verification requires the secret key or public key used to sign the token.
Is it safe to decode JWTs here?
The decoding happens entirely in your browser — tokens are not sent to any server. However, avoid pasting production tokens with sensitive user data into any online tool.