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HMAC Generator

Generate HMAC with various algorithms - Client-side processing

What is HMAC Generator?

Generate HMAC (Hash-based Message Authentication Code) signatures with our free HMAC Generator. Create HMAC-MD5, HMAC-SHA1, HMAC-SHA256, and HMAC-SHA512 signatures for API authentication, webhook verification, and data integrity validation. Used by AWS, Stripe, GitHub, and other major APIs.

How to Use HMAC Generator

1

Enter the message or data to sign.

2

Enter the secret key for HMAC computation.

3

Select the hash algorithm (SHA-256 recommended).

4

Click 'Generate' to create the HMAC signature.

Key Features

HMAC-MD5, SHA1, SHA256, SHA384, SHA512 support
Hex and Base64 output formats
Works for API signature verification
Handles multi-line and binary messages
Client-side computation for key security

Frequently Asked Questions

What is HMAC used for?

HMAC is used to simultaneously verify data integrity and authenticity. It's commonly used in API authentication (AWS Signature V4), webhook verification (Stripe, GitHub), JWT signing, and secure communication protocols.

How is HMAC different from a regular hash?

A regular hash only uses the message as input and anyone can compute it. HMAC uses both a message and a secret key, so only parties who know the key can generate or verify the signature. This proves both integrity and authenticity.

Which HMAC algorithm should I use?

HMAC-SHA256 is the most widely recommended. It provides strong security and is required by most modern APIs. HMAC-SHA1 is still acceptable but being phased out. Avoid HMAC-MD5 for new implementations.