Cognomen กุลแจ (กุลแจ 
) , across the world, is an extremely rare surname. The last name กุลแจ is characteristic of South-eastern Asia, particularly Thailand, where it is an extremely rare surname. Likewise, กุลแจ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| กุลแจ | Thailand |