SHA512

SHA-512 is a cryptographic hash function in the SHA-2 family, designed by the National Security Agency (NSA) and published by the National Institute of Standards and Technology (NIST) in 2001. It takes an input of arbitrary length and returns a 512-bit (64-byte) digest. It is not encryption and has no secret key; it is a one-way function intended for data integrity, authentication, and digital signatures. It is deterministic: the same input yields the same hash.

SHA-512 processes messages in 1024-bit blocks and uses 64 rounds of compression with 64-bit words. It maintains eight 64-bit chaining variables and uses a defined sequence of constants. The digest is produced by concatenating the final values of these variables. It is part of the SHA-2 family, which also includes SHA-224, SHA-256, SHA-384, and the truncated variants SHA-512/224 and SHA-512/256. SHA-512 produces a 512-bit output, represented as 128 hexadecimal characters.

Common uses include generating digital signatures with RSA or ECC, creating HMACs (HMAC-SHA-512), and producing data fingerprints. For password storage, SHA-512 alone is not ideal; dedicated password hashing or key derivation functions such as Argon2, bcrypt, or scrypt are preferred with proper salting and iteration counts.

Security-wise, SHA-512 is considered strong and resistant to known practical collisions or preimages, though no hash function is provably secure. Its 512-bit output provides substantial collision resistance, and implementations exist in standard cryptographic libraries across platforms.