RIPEMD (RACE Integrity Primitives Evaluation Message Digest) is an N-bit message digest algorithm and cryptographic hash function. RIPEMD is based upon the design principles used in MD4, and is similar in performance to the more popular SHA-1


RIPEMD-128 is a plug-in substitute for RIPEMD (or MD4 and MD5, for that matter) with a 128-bit result. In the view of some, 128-bit hash results do not offer sufficient protection, and applications using 128-bit hash functions should consider upgrading to a 160-bit function.


RIPEMD-160 is a strengthened version of RIPEMD with a 160-bit hash result. The design philosophy is to build as much as possible on experience gained by evaluating MD4, MD5, and RIPEMD. Like its predecessors, RIPEMD-160 is tuned for 32-bit processors.

RIPEMD-160 was designed in the open academic community, in contrast to the NSA-designed family of algorithms, SHA. On the other hand, RIPEMD-160 appears to be used somewhat less frequently than SHA-1, which may have caused it to be less scrutinized than SHA-1.


RIPEMD-256 and RIPEMD-320 are optional extensions of RIPEMD-128 and RIPEMD-160, respectively, and are intended for applications of hash functions that require a longer hash result without needing a higher security level. The 256 and 320-bit versions diminish the chance of accidental collision compared to RIPEMD-128 and RIPEMD-160 while offering the same level of security.
