Cognomen จันไทย (Chanthai 
, จันไทย , Janthai 
) , around the world, is a rare last name. The surname จันไทย is habitual in Thailand, where it is quite a rare surname, Switzerland, where it is a rare surname, and Croatia, where it is a very rare surname. Not in comparison with a country's population, it most frequently occurs in Thailand, Switzerland, and the United States. Likewise, จันไทย is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Chanthai | Thailand, Laos, United States, India, Cambodia |
| จันไทย | Thailand |
| Janthai | Colombia, Thailand, United States, India, Switzerland |
| Chan Thai | Malaysia |