Surname Клайн (Cline 
, Klajn 
, Clyne , and others...) , globally, is a common cognomen. The last name Клайн is habitual in Grenada, where it is a common surname, the United States, where it is quite a common surname, and Ireland, where it is quite a rare surname. Not in comparison with a country's population, it most frequently occurs in the United States, Canada, and the United Kingdom. Much less frequently, Клайн is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Clyne, Cline | United Kingdom, Australia, United States, Canada, France |
| Klajn | United Kingdom, Australia, United States, Poland, Canada |
| Klayn | Philippines, Bulgaria, United States, India, Brazil |
| Клайн | Kazakhstan, Russia, Kyrgyzstan, Bulgaria, Ukraine |