Surname ไช (Chai 
, Chay 
, Chhai 
) , throughout the world, is a widespread cognomen. The last name ไช is characteristic of Malaysia, where it is a common surname, British Virgin Islands, and Singapore (explore the name in all countries). Measured by absolute frequency, the name is most common in China, Malaysia, and Myanmar. Very seldom, ไช is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Chai | Myanmar, Singapore, Indonesia, Malaysia, China |
| Chay | Myanmar, Indonesia, Guatemala, Malaysia, China |
| Chhai | Australia, Thailand, United States, India, Malaysia |
| ไช | Thailand |