Runjak families are Croats and they are mostly from Zlatar. In the past century, relatively most of Croatian residents bearing this family name were born in Zlatar and Zagreb.
Prevalence
About 120 people with faimily name Runjak live in Croatia today, in 50 households. There were 130 of them in the middle of the past century, and their number decreased by 10 percent. They are located in 10 Croatian counties, in 10 cities and 22 other places, mostly in Belec (30), Zagreb (25), Virovitica (<10), Varazdin (<10), and in Zlatar (<10).
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.