Jadek families are Croats and they are mostly from Zabok area. In the past century, relatively most of Croatian residents bearing this family name were born in Zabok and Slatina.
Prevalence
About 80 people with faimily name Jadek live in Croatia today, in 30 households. There were 70 of them in the middle of the past century, and their number increased by 0 percent. They are located in 7 Croatian counties, in 8 cities and 12 other places, mostly in Slatina (20), Zabok (20), Donja Pacetina in Zabok area (<10), Zagreb (<10), and in Vrbovec (<5).
Outside Croatia
Family name Jadek (including: Yadek , Jadeck ) is present in five countries on three continents. "Jadeck " is used by few people in the United States.
In the sources analysed in the project Acta Croatica so far, the name is mentioned few times, the first time 2007 in source Encyclopaedia of Croatian Surnames.