Surname Koskar (Koskar 
) , all around the world, is a rare family name. The cognomen Koskar is characteristic of Hungary, where it is quite a rare surname, Estonia, where it is a rare surname, and Turkey, where it is a very rare surname. Measured by absolute frequency, this name is the most popular in Hungary, Turkey, and Germany. Very seldom, Koskar is the forename as well as the last name.