Cryptography · Local browser tool

HMAC Generator and Verifier

Generate or compare an HMAC using a local secret and the Web Crypto API.

Input stays on this deviceNo sign-upStandard-linked guidance

Use the tool

Enter only data you are authorised to inspect. The result is a focused technical check, not a certification or full vulnerability assessment.

What it checks

Clear scope. Reproducible output.

  • HMAC-SHA-256, 384 and 512
  • Hex output and optional comparison
  • Secret is never submitted or stored

Questions

Does HMAC Generator and Verifier upload my input?

No. The working tool runs in the current browser tab. Avoid browser extensions or shared devices when handling sensitive material.

Does a passing result prove my system is secure?

No. It proves only the checks described on this page against the input you supplied. Server behaviour, business logic and runtime vulnerabilities require separate authorised testing.

Why is the result different from a live scanner?

This tool analyses pasted or local data. A live scanner observes network responses, DNS, TLS and redirects, so its evidence and scope are different.