Kralj families are Croats and they are mostly from Zagreb. According to some sources they are from Martinscina near Zlatara. In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and Varazdin. In Gornja Konjščina in Zlatar area every fourth inhabitant had the family name Kralj.
About 4200 people with faimily name Kralj live in Croatia today, in 1700 households. There were 4400 of them in the middle of the past century, and their number remains constant. They are located in all Croatian counties, in 88 cities and 454 other places, mostly in Zagreb (1030), Varazdin (95), Dubrovnik (75), Karlovac (70), and in Osijek (60).