Surname Selnik (Selnik 
) , all around the world, is a rare last name. The cognomen Selnik is habitual in Czechia, where it is a rare surname, Croatia, and Germany, where it is a very rare surname. In absolute terms, it is the most numerous in Czechia, Croatia, and the United States. Very seldom, Selnik is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Selnik | Germany, Croatia, United States, Czechia, Argentina |