List of hash functions

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This is a list of hash functions including cyclic redundancy checks, checksum functions, and cryptographic hash functions.

Contents 1 Cyclic redundancy checks 2 Checksums 3 Cryptographic hash functions 4 Computational costs of CRCs vs Hashes

[edit] Cyclic redundancy checks

Main article: Cyclic redundancy check

Name	Length	Type
Adler-32	32 bits	specific
bsd	16 bits	CRC
checksum	32 bits	CRC
crc16	16 bits	CRC
crc32	32 bits	CRC
crc32 mpeg2	32 bits	CRC
crc64	64 bits	CRC
UNIX V checksum	16 bits	CRC

Adler-32 is often classified as a CRC, but it uses a different algorithm. For more details, see the main article.

[edit] Checksums

Main article: Checksums

Name	Length	Type
sum8	8 bits	sum
sum16	16 bits	sum
sum24	24 bits	sum
sum32	32 bits	sum
xor8	8 bits	sum

[edit] Cryptographic hash functions

Main article: cryptographic hash function

Name	Length	Type
elf64	64 bits	hash
HAVAL	128 to 256 bits	hash
MD2	128 bits	hash
MD4	128 bits	hash
MD5	128 bits	hash
RIPEMD-64	64 bits	hash
RIPEMD-160	160 bits	hash
RIPEMD-320	320 bits	hash
SHA1	160 bits	hash
SHA256	256 bits	hash
SHA384	384 bits	hash
SHA512	512 bits	hash
Tiger	192 bits	hash
WHIRLPOOL	512 bits	hash

[edit] Computational costs of CRCs vs Hashes

Checksum Algorithm	Relative Cost
32-bit Adler	1.00
32-bit CRC (IEEE)	1.46
64-bit CRC (ISO)	2.23
128-bit CRC	2.29
128-bit MD4	4.48
128-bit MD5	4.51

Note that 128-bit MD4 is 1.96 times as expensive as 128-bit CRC.

There is considerable variation in these numbers depending on CPU type and memory usage. MD4 is considerably slower on big-endian processors than little-endian, whereas CRCs are endian agnostic. CRC algorithms also readily scale in speed with additional memory. CRC32 with 4kb of tables runs in approximately 44% of the time that CRC32 does with 1kb of tables. Most hashes can also have their code unrolled to improve speed at expense of code size, but the effects are less dramatic.