JWT Decoder — Decode Tokens Instantly
Paste a JSON Web Token to decode and inspect its header, payload, and expiration. 100% private — never leaves your browser.
Free Online JWT Decoder
Decode JSON Web Tokens (JWT) instantly without any server-side processing. View the header algorithm, payload claims, expiration time, and signature. Your tokens never leave your browser — completely secure and private.
Perfect for debugging authentication flows, inspecting API tokens, and verifying token expiration during development.
Frequently Asked Questions
Is it safe to paste my JWT token here?
Yes. The decoding happens entirely in your browser using JavaScript. Your token is never sent to any server.
What parts of a JWT can I see?
You can see the header (algorithm, type), payload (claims like sub, exp, iat), and the signature hash.
Can this tool verify JWT signatures?
This tool decodes and displays the token contents. Signature verification requires the secret key which should never be shared in a browser tool.
What is a JWT token?
A JSON Web Token (JWT) is a compact, URL-safe token used for authentication and information exchange between parties. It contains a header, payload, and signature.