About the HMAC Generator
The HMAC Generator imports a UTF-8 secret into Web Crypto and signs the exact message with a standard keyed-hash construction. Unlike a plain digest, the result proves knowledge of the shared key.
How to use the HMAC Generator
- Enter the message and shared secret exactly.
- Choose the agreed SHA family and output encoding.
- Generate and compare the code without exposing the secret.
Practical tips
- Do not use a production secret on a shared or untrusted device.
- Both parties must use identical bytes, algorithm and encoding.