Family name ไซย์ (Sai 
, ไซย์ 
) , in the entire world, is a widespread last name. The surname ไซย์ is habitual in Mongolia, where it is a prevalent surname, Myanmar, where it is a common surname, and Malaysia, where it is quite a common surname (explore the name in all countries). Measured by absolute frequency, it most frequently occurs in Myanmar, India, and Mongolia. More frequently, ไซย์ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Sai | China, Mongolia, Malaysia, India, Myanmar |
| ไซย์ | Thailand |