Hash Algorithms

In the Volume Creation Wizard, in the password change dialog window, and in the Keyfile Generator dialog window, you can select a hash algorithm when using PBKDF2-HMAC as the key derivation function. When Argon2id is selected as the key derivation function, no hash algorithm selection is available as Argon2id uses its own internal BLAKE2b hash function.

For PBKDF2-HMAC, the user-selected hash algorithm is used by the VeraCrypt Random Number Generator as a pseudorandom "mixing" function, and by the header key derivation function (HMAC based on a hash function, as specified in PKCS #5 v2.0) as a pseudorandom function. When creating a new volume, the Random Number Generator generates the master key, secondary key (XTS mode), and salt. For more information, please see the section Random Number Generator and section Header Key Derivation, Salt, and Iteration Count.