6 chars
Hex
Base64
Base64url

💡 About HMAC

HMAC (Hash-based Message Authentication Code) uses a cryptographic hash function and a secret key to verify both message integrity and authenticity. Unlike a plain hash, HMAC cannot be forged without knowing the key.

Common Uses

API request signing · JWT signatures (HS256/HS384/HS512) · Webhook payload verification · Cookie integrity checks