RIPEMD-256 (256 bit) is (RACE Integrity Primitives Evaluation Message Digest). RIPEMD-256 is part of message digest family (cryptographic hash functions) developed in Leuven, Belgium, by Hans Dobbertin, Antoon Bosselaers and Bart Preneel at the COSIC research group at the Katholieke Universiteit Leuven, and first published in 1996. RIPEMD was based upon the design principles used in MD4, and is similar in performance to the more popular SHA-1.

The 256-bit RIPEMD-256 hashes (also termed RIPE message digests) are typically represented as 64-digit hexadecimal numbers.