Security Audit JWT Tokens
Review JWTs as part of a security audit — check for weak signing algorithms, excessive token lifetimes, or sensitive data in the payload.
🔒 The token is decoded entirely in your browser. Nothing is sent to any server.
Security Audit tips
Check the `alg` field in the header. `none` or `HS256` with a short secret is a red flag; production tokens should use `RS256`, `ES256`, or stronger.
Long-lived tokens (more than a few hours for access tokens) are a security concern. Look at the gap between `iat` and `exp` to assess token lifetime.
Look at the payload — JWTs should never contain passwords, full credit card numbers, or other sensitive data. The payload is essentially plaintext (Base64URL ≠ encrypted).
The decoder runs entirely client-side, so it's safe to audit production tokens here without any data leaving your network or browser session.
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