Surname Ryva (Рива 
, Ryva 
) , across the world, is a very rare last name. The cognomen Ryva is habitual in Czechia, where it is a rare surname, Kazakhstan, where it is a very rare surname, and Kyrgyzstan. Measured by absolute frequency, the name is most common in Russia, Czechia, and the United States. More prevalently, Ryva is the forename as well as the last name.