Last name Kudja (Kudja 
, Кудя 
) , in all the world, is a rare surname. The surname Kudja is characteristic of Slovakia, where it is a rare surname, Belarus, where it is a very rare surname, and Thailand. Not in comparison with a country's population, it is commonest in Russia, Thailand, and Ukraine. Very seldom, Kudja is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Kudja | Philippines, United States, Thailand, India, Slovakia |
| Кудя | Kazakhstan, Russia, Ukraine, Belarus |