Last name Ривай (Rivai 
, Rivay 
, Rivaj 
) , in the entire world, is a common cognomen. The family name Ривай is characteristic of Indonesia, where it is quite a rare surname, Maldives, and Malaysia, where it is a rare surname. Not in comparison with a country's population, it is the most numerous in Indonesia, India, and Malaysia. Much less frequently, Ривай is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Rivai | Democratic Republic of the Congo, Malaysia, Indonesia, United States, India |
| Rivay | Indonesia, India, United States, Brazil, Mexico |
| Rivaj | South Africa, India, Maldives, United States |
| Ривай | Russia, Ukraine |