Most popular Croatian name is definitely Ivan, and variations of that name. Ivan is a name for boys. In English, it is the same as John.
Ivan can come in many variations. They could be Ivo, Ivano and Ivica for boys, or Ivana, Iva, Ivona for girls. “I” in those names is read like ee in week, not like i in ivy.
Other popular Croatian names for boys are Luka (Luke), Marko (Mark), Filip (Phillip), Josip (Joseph), Antonio (Anthony), Karlo (Carl), Petar (Peter), and so on. Most of these names are traditional and exist in Croatian language for a long time.
For girls, besides Iva and Ivana, the most popular names are Ana (Anne) and Marija (Mary). There are cases when in one school class with 20 children, there are three or four girls named Marija, or three or four boys names Ivan.
Other popular names for girls are Lucija (Lucy), Mia, Lana, Nika, Dora, Sara, Katarina, Martina, Marina, and so on.