Last name Casai (Casai 
) , around the world, is a very rare cognomen. The last name Casai is characteristic of Italy, where it is a very rare surname, Argentina, and the United States, where it is an extremely rare surname. Much less frequently, Casai is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Casai | Italy, Mexico, United States, Argentina, France |