Comparison of Hash Methods

A cryptographic hash function is a hash function that takes an arbitrary block of data and returns a fixed-size bit string, the cryptographic hash value, such that any (accidental or intentional) change to the data will (with very high probability) change the hash value. The data to be encoded are often called the message, and the hash value is sometimes called the message digest or simply digest.

Hash Algorithm	Output Size (bits)	Internal State (bits)	Block Size (bits)	Rounds	Security
SHA1	128	128	512	80	More secure than MD5. According to Wikipedia article: Cryptographic weaknesses were discovered in SHA-1, and the standard was no longer approved for most cryptographic uses after 2010..
SHA256	256	256	512	64	More secure than SHA1. Takes somewhat longer to produce.
SHA384	384	512	1024	64	More secure than SHA256. Takes somewhat longer to produce.
SHA512	512	512	1024	64	More secure than SHA384. Takes somewhat longer to produce.
SHA224	224	256	512	64	Somewhat faster than SHA256
MD5	128	128	512	64	Security is described in Wikipedia as “severely compromised”.
MD2	128	-	128	18	Optimized for 8-bit computers. Should be avoided, if possible. No longer considered secure.
RIPEMD160	160				Similar in performance to SHA1 Less used than SHA1 Output size less than SHA256.

NOTE: SHA (Secure Hash Algorithm) variations listed above were designed by the NSA.