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Decode JSON Web Tokens (JWT) and view header, payload, and signature. Check token expiration.
Paste the JWT string you want to decode into the input field. Or use the Sample button to load a test token.
Review the JSON contents broken down into header, payload, and signature sections. Timestamps are shown in readable date format.
Use the copy button in each section to copy the header or payload JSON to your clipboard.
Security Warning
This tool only decodes JWTs and does not verify signatures. Validate token authenticity separately.
All processing happens in your browser. Tokens are never sent to any server.
JWT Decoder is an online tool that decodes JSON Web Tokens (JWT) and displays their contents. It breaks down the token into header, payload, and signature parts, displaying them in formatted JSON. Timestamp claims like expiration (exp) and issued at (iat) are shown in human-readable date format. All processing happens in your browser—tokens are never sent to any server.
No, this tool only decodes JWTs and does not verify signatures. Signature verification requires secret or public keys, which is not included for security reasons.
No, all processing happens entirely in your browser. Your token is never sent to any server.
Yes, expired tokens can still be decoded and displayed. A warning will be shown indicating the token has expired.
JWT (JSON Web Token) is a compact token format for securely transmitting information between parties. It consists of three parts—header, payload, and signature—which are Base64URL-encoded JSON strings joined by dots (.).