Family name كلاك (Klak 
, Clack 
, كلاك 
) , throughout the world, is quite a common cognomen. The family name كلاك is habitual in Reunion, where it is quite a common surname, Bosnia and Herzegovina, where it is quite a rare surname, and the United Kingdom. In absolute terms, it most frequently occurs in the United States, the United Kingdom, and Poland. Likewise, كلاك is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Klak | Australia, South Africa, Poland, United Kingdom, United States |
| Clack | Australia, South Africa, Canada, United Kingdom, United States |
| كلاك | Syria |
| Klakk | United States |