Worldwide, Rosler-Koslar (Rosler-Koslar 
) is an extremely rare unknown gender first name. Much more prevalently, Rosler-Koslar is the last name as well as the forename. Parts of the name also exists independently as a last name Rosler, and a last name Koslar.
| VARIANT | COUNTRY |
|---|---|
| Rosler-Koslar | Germany |