Surname Tonkaya (Tonkaya 
, Тонкая 
) , all over the world, is a rare family name. The last name Tonkaya is characteristic of Belarus, where it is a rare surname, Russia, and Turkey, where it is a very rare surname. Very seldom, Tonkaya is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Tonkaya | Russia, India, Turkey |
| Тонкая | Russia, Ukraine, Kazakhstan, Belarus |