In all the world, Juan Giancarlo (Juan Giancarlo 
) is a very rare masculine given name. The first name Juan Giancarlo is habitual in Latin America and the Caribbean, particularly Peru, where it is a very rare boy's name. Very seldom, Juan Giancarlo is the last name as well as the forename.
| VARIANT | COUNTRY |
|---|---|
| Juan Giancarlo | Peru, Spain |
Vargas, and Vargas De La Cruz