Surname จอนใจ (Jonjai 
, จอนใจ , Jhonjai) , worldwide, is a very rare last name. The family name จอนใจ is habitual in Thailand, where it is a very rare surname, and the United States, where it is an extremely rare surname. Much less frequently, จอนใจ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Jonjai | United States, Thailand |
| จอนใจ | Thailand |