100% Client-Side No data leaves your browser

HMAC Calculator

Calculate Keyed-Hash Message Authentication Code (HMAC) using SHA-256 or SHA-1 — hex key & data input

🔏 Input

Enter your secret key as hex bytes (e.g. 4a656665 for "Jefe"). Spaces are allowed.

Enter hex data to authenticate (e.g. 4869205468657265 for "Hi There"). Spaces are allowed.

Related Tools

🔐

SHA-256 Calculator

Calculate SHA-256 hash digest (256-bit) of hex string input
🔒

SHA-1 Calculator

Calculate SHA-1 hash digest (160-bit) of hex string input
🔑

KCV Calculator

Calculate Key Check Values for 3DES and AES keys
📖 About This Tool

What is the HMAC Calculator?

The HMAC Calculator computes Keyed-Hash Message Authentication Codes using SHA-256 or SHA-1 algorithms. HMAC provides both data integrity verification and message authentication using a shared secret key.

🛠️ How to Use
  1. Select the hash algorithm (SHA-256 or SHA-1).
  2. Enter your hexadecimal key.
  3. Enter your hexadecimal data.
  4. Click Calculate to compute the HMAC.
❓ FAQ

What is HMAC?

HMAC (Hash-based Message Authentication Code) combines a cryptographic hash function with a secret key to produce a message authentication code. It verifies both data integrity and authenticity.