HKDF (SHA-256) Key Expansion

HKDF expands key material; it is not a password hasher by itself.

About HKDF

HKDF is a standard for deriving strong keys from initial keying material using HMAC as a PRF. It is commonly used to expand shared secrets into multiple keys.

HKDF online  HMAC-based key derivation (in-browser, no upload)

FAQs

What does HKDF do?
It extracts and expands key material using HMAC, turning a shared secret into strong keys.
Is HKDF a password hasher?
No. Use bcrypt/scrypt/Argon2 for password hashing; HKDF is for key expansion.
Does this tool upload my data?
No. HKDF derivation runs entirely in your browser.

HKDF key derivation FAQs

FAQs

Extract and expand?
HKDF has two phases; extract with salt/IKM, then expand with info/context.