Cognomen Rudniak (Rudniak 
) , in the world, is a rare family name. The surname Rudniak is characteristic of Poland, where it is a rare surname, Denmark, where it is a very rare surname, and Brazil. Likewise, Rudniak is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Rudniak | Denmark, United States, Poland, France, Brazil |