Family name กานต์สิร (กานต์สิร 
) , in the world, is an extremely rare last name. The cognomen กานต์สิร is habitual in South-eastern Asia, particularly Thailand, where it is an extremely rare surname. More frequently, กานต์สิร is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| กานต์สิร | Thailand |