The Secure Hash Algorithms are a family of cryptographic hash functions published by the National Institute of Standards and Technology (NIST) as a U.S. Federal Information Processing Standard (FIPS), including:
The corresponding standards are FIPS PUB 180 (original SHA), FIPS PUB 180-1 (SHA-1), FIPS PUB 180-2 (SHA-1, SHA-256, SHA-384, and SHA-512). NIST has updated Draft FIPS Publication 202, SHA-3 Standard separate from the Secure Hash Standard (SHS).
In the table below, internal state means the "internal hash sum" after each compression of a data block.
| Algorithm and variant | Output size (bits) |
Internal state size (bits) |
Block size (bits) |
Rounds | Operations | Security (bits) |
Performance on Skylake (median cpb) | First published | ||
|---|---|---|---|---|---|---|---|---|---|---|
| Long messages | 8 bytes | |||||||||
| MD5 (as reference) | 128 | 128 (4 × 32) | 512 | 4 (16 operations in each round) | And, Xor, Or, Rot, Add (mod 232) | ≤ 18 (collisions found) | 4.99 | 55.00 | 1992 | |
| SHA-0 | 160 | 160 (5 × 32) | 512 | 80 | And, Xor, Or, Rot, Add (mod 232) | < 34 (collisions found) | ≈ SHA-1 | ≈ SHA-1 | 1993 | |
| SHA-1 | < 63 (collisions found) | 3.47 | 52.00 | 1995 | ||||||
| SHA-2 | SHA-224 SHA-256 | 224 256 | 256 (8 × 32) | 512 | 64 | And, Xor, Or, Rot, Shr, Add (mod 232) | 112 128 | 7.62 7.63 | 84.50 85.25 | 2004 2001 |
| SHA-384 | 384 | 512 (8 × 64) | 1024 | 80 | And, Xor, Or, Rot, Shr, Add (mod 264) | 192 | 5.12 | 135.75 | 2001 | |
| SHA-512 | 512 | 256 | 5.06 | 135.50 | 2001 | |||||
| SHA-512/224 SHA-512/256 | 224 256 | 112 128 | ≈ SHA-384 | ≈ SHA-384 | 2012 | |||||
| SHA-3 | SHA3-224 SHA3-256 SHA3-384 SHA3-512 | 224 256 384 512 | 1600 (5 × 5 × 64) | 1152 1088 832 576 | 24 | And, Xor, Rot, Not | 112 128 192 256 | 8.12 8.59 11.06 15.88 | 154.25 155.50 164.00 164.00 | 2015 |
| SHAKE128 SHAKE256 | d (arbitrary) d (arbitrary) | 1344 1088 | min(d/2, 128) min(d/2, 256) | 7.08 8.59 | 155.25 155.50 | |||||
All SHA-family algorithms, as FIPS-approved security functions, are subject to official validation by the CMVP (Cryptographic Module Validation Program), a joint program run by the American National Institute of Standards and Technology (NIST) and the Canadian Communications Security Establishment (CSE).