Cognomen ฐิน (Thin 
, ฐิน 
) , around the world, is a widespread last name. The surname ฐิน is characteristic of Mongolia, where it is a prevalent surname, Myanmar, where it is a common surname, and Malaysia, where it is quite a common surname. Also, ฐิน is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Thin | Indonesia, Myanmar, Vietnam, Mongolia, Malaysia |
| ฐิน | Thailand |