bcrypt has a fixed output size, which makes it less than perfect for generating encryption keys from passwords. That's the primary function of PBKDF2, while bcr

bcrypt has a fixed output size, which makes it less than perfect for generating encryption keys from passwords. That's the primary function of PBKDF2, while bcrypt is mostly used for simply comparing hashes. You could also feed the output of bcrypt into PBKDF2, but as far as I'm aware, nobody is recommending against straight PBKDF2/SHA256 for key derivation.