Sign a JSON payload into a JWT (JSON Web Token) using an HMAC secret — useful for testing APIs and auth flows that expect a JWT.
Frequently asked questions
No — treat this as a testing/debugging tool only. Never paste a real production signing secret into any third-party website, including this one; use a throwaway test secret instead.
A JSON object with whatever claims your application needs — e.g. {"sub": "user123", "role": "admin"}. Standard claims like exp (expiry) and iat (issued-at) are yours to include manually if needed.