HMAC Generator
Generate HMAC signatures with the Web Crypto API — nothing is sent to a server
Input
Message and secret key
HMAC
SHA-256 · hex
—Frequently asked questions
Related guides
Encryption Tools Explained: AES vs BCrypt vs HMAC
Three cryptographic primitives developers constantly confuse — reversible encryption (AES), password hashing (BCrypt), and message signing (HMAC). What each one is for, and how to pick correctly.
JSON Web Tokens (JWT) Explained: A Complete Guide for Developers
What a JWT is, how the header.payload.signature structure works, which claims matter, and how to sign and verify tokens securely — with examples you can run in your browser.
Generating Secure API Tokens and Secrets in the Browser
How to create cryptographically strong tokens, sign payloads with HMAC, and encrypt data with AES — all client-side, with nothing sent to a server.
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