Cognomen Tünn (Tunne 
, Tünn) , in the entire world, is a very rare last name. The surname Tünn is habitual in Latvia, where it is a rare surname, Australia, where it is a very rare surname, and Turkey, where it is an extremely rare surname. In absolute terms, the name is most common in Australia, India, and Latvia. More frequently, Tünn is the forename as well as the last name.