HMAC Generator

Easily compute a Hash-based Message Authentication Code (HMAC) using WebCrypto.

Secret Key *

Symmetric secret key used for signing.

Message Payload *

Hash Algorithm

Understanding HMAC Authentication

A Hash-based Message Authentication Code (HMAC) is a highly secure cryptographic authentication technique that utilizes a cryptographic hash function alongside a secret key. This unique pairing provides dual assurances: data integrity (the message hasn't been altered) and authenticity (the sender possesses the private key).

Modern APIs, RESTful services, and webhooks frequently use HMACs (particularly HMAC-SHA256) to sign their HTTP requests securely. Our generator leverages the completely offline `SubtleCrypto` API directly in your browser, meaning your secret configuration keys are never broadcasted over networks.

HMAC Generator

Computed HMAC Output (Hexadecimal)

Understanding HMAC Authentication