Family name Клас (Klaas 
, Claes , Klas , and others...) , all over the world, is a common surname. The surname Клас is characteristic of Belgium, where it is a common surname, Aland Islands, where it is quite a common surname, and Suriname (explore the name in all countries). Measured by absolute frequency, this name is the most popular in Belgium, South Africa, and Germany. Likewise, Клас is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Claes, Klaas, Klas | Belgium, Netherlands, Germany, Sweden, South Africa |
| Clas | Netherlands, Germany, South Africa, Sweden, United States |
| Клас | Kazakhstan, Russia, Kyrgyzstan, Ukraine |
Claas, Claesz, Classe, Claus, Claës, Heda, Klasová, Klass, Klaus, Klausová, Nicholas, Nicolaas, Nikolass, Van, Κλάους, Νίκολας, Νικόλαος, Νικόλας, Клаас, Класс, Клаус, Мікалай, Никола, Николаев, Николас, Ніколас, ניקולס, קלאוס, كلاس, كلاوز, كلاوس, كلايس, كلوز, كلوس, نيكولاس, ნიკოლასი, クラウス, クレス, ニコラス, 克拉斯, 尼古拉斯, and 尼古拉耶夫
| клас, анна иосифовна Estonian pianist, EE (b. 1912) |
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