Last name Koolin (Koolin 
) , in all the world, is an extremely rare surname. The surname Koolin is habitual in Israel, where it is a very rare surname, the United States, where it is an extremely rare surname, and Brazil. Also, Koolin is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Koolin | Israel, Brazil, United States, Philippines |