Surname Каелин (Kaelin 
, Каелин 
) , in the entire world, is quite a rare family name. The surname Каелин is characteristic of Western Europe, particularly Liechtenstein, where it is quite a common surname, Switzerland, where it is quite a rare surname, and Austria, where it is a rare surname. In absolute terms, it is the most numerous in the United States, Switzerland, and France. Much less frequently, Каелин is the forename as well as the last name.