Cognomen Kaplunskii (Kaplunskii 
, Каплунский 
) , in the world, is a rare surname. The cognomen Kaplunskii is habitual in Belarus, where it is a rare surname, Kazakhstan, where it is a very rare surname, and Russia.
| VARIANT | COUNTRY |
|---|---|
| Kaplunskii | Russia, Belarus |
| Каплунский | Kazakhstan, Russia, Ukraine, Belarus |