HMAC Signature Generator

What is HMAC?

HMAC (Hash-based Message Authentication Code) is a cryptographic method that combines a message with a secret key using a hash function. It verifies both data integrity and authenticity — confirming the message hasn't been tampered with and was sent by someone who knows the secret key.

Use Cases

• Webhook signature verification (Stripe, GitHub, Slack)
• API request signing and authentication
• JWT token generation with HS256/384/512
• Data integrity verification
• Secure token generation for password resets
• Cloud service authentication (AWS Signature V4)