Last name ดุลยนัย (ดุลยนัย 
) , in all the world, is a very rare surname. The cognomen ดุลยนัย is habitual in South-eastern Asia, particularly Thailand, where it is a very rare surname. Likewise, ดุลยนัย is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| ดุลยนัย | Thailand |