Cognomen สินทัย (สินทัย 
, Sinthai 
) , in all the world, is a very rare surname. The family name สินทัย is characteristic of South-eastern Asia, particularly Thailand, where it is a very rare surname. More frequently, สินทัย is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| สินทัย | Thailand |
| Sinthai | India, United States, Thailand |