Paste a compact JSON Web Token to inspect its decoded JSON header, payload, signature-segment length, and common numeric date claims.
By Josh Liljenquist•
Enter input to begin.
Result
Method
JWT header and payload segments use Base64URL. The tool converts each segment to bytes, requires valid UTF-8, and parses each as a JSON object. The signature segment is described but never verified.
Limits and assumptions
A token must contain exactly three nonempty segments and stay within 2 MB. Decoding shows what a token contains. It does not verify that the token is valid, trusted, or untampered. Avoid pasting production secrets into any tool you do not trust.