Cognomen Schlak (Schlak 
) , in the world, is a rare family name. The family name Schlak is characteristic of Germany, where it is a rare surname, Austria, and Argentina. Measured by absolute frequency, it is commonest in Germany, the United States, and Argentina. Much less frequently, Schlak is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Schlak | Germany, Poland, Canada, United States, Argentina |
| stephan schlak DE (b. 1974) |
|