Gmaz families are Croats and they are mostly from Oroslavje. In the past century, relatively most of Croatian residents bearing this family name were born in Zagreb and Oroslavje.
Prevalence
About 100 people with faimily name Gmaz live in Croatia today, in 40 households. There were 130 of them in the middle of the past century, and their number decreased by 20 percent. They are located in 6 Croatian counties, in 9 cities and 8 other places, mostly in Zagreb (30), Oroslavje (25), Stubicke Toplice in Oroslavje area (10), Velika Gorica (<10), and in Voloder in Kutina area (<10).
Outside Croatia
Family name Gmaz is present in 10 countries worldwide. The family name "Gmaz " is used by small number of people in the United States.
In the sources analysed in the project Acta Croatica so far, the name is mentioned over twenty times, the first time 1902 in source Hartmann's General List of Apartments in Zagreb.