HMAC Generator - Calculate Keyed-Hash Message Authentication Codes
Generate HMAC-SHA256, HMAC-SHA512, and HMAC-MD5 keyed digests from input messages and secret keys for API authentication.
This tool runs in your browser.
Processed locally.
How to use
- 01Enter a secret and message.
- 02Generate HMAC.
FAQ
What is HMAC and how does it differ from regular hashing?
HMAC incorporates a cryptographic secret key alongside the message, providing authentication and integrity while preventing length extension attacks.
Which HMAC algorithm is standard for REST API signatures?
HMAC-SHA256 is the standard mechanism implemented by major cloud providers including AWS, Stripe, GitHub, and Shopify webhooks.
Is it safe to test private API secret keys here?
Yes. Key processing and HMAC computations execute purely within browser memory without transmission over external connections.