Family name ไจย (Chai 
, ไจย 
) , in the entire world, is a widespread cognomen. The cognomen ไจย 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, it most frequently occurs in China, Malaysia, and Indonesia. Very seldom, ไจย is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Chai | China, Singapore, Malaysia, Indonesia, Myanmar |
| ไจย | Thailand |