JSON Web Token (JWT) Header & Claims Inspector
Decodes and inspects JWT header and payload claims segments without secret verification.
Notice: engineering verification utility. Use test or de-identified data and verify results independently before relying on them.
How it works
Standard: RFC 7519 JSON Web Token (JWT)
Formula: Base64Url decode header (segment 1) and payload claims (segment 2)
Checks: Three dot-separated JWT string segments
Calculated locally in browser memory; nothing leaves your browser.
Deterministic local-first client-side execution. Provided as-is without warranty.