HMAC Generator

HMAC (Hash-based Message Authentication Code):

• Combines a hash function with a secret key for message authentication
• Provides both integrity and authenticity verification
• Resistant to length extension attacks
• Widely used in API authentication and digital signatures

Formula: HMAC = H((K ⊕ opad) || H((K ⊕ ipad) || message))

Security: Security depends on both the hash function and secret key strength

Common Uses: JWT tokens, API authentication, message integrity