It depends on countries, and within countries it depends on the location. In Italy 28 m2 (roughly 300 sqft) is the minimum size you can legally call it a livin

It depends on countries, and within countries it depends on the location. In Italy 28 m2 (roughly 300 sqft) is the minimum size you can legally call it a living unit, "tiny" is usually roughly 30-60 m2, "medium" is 60-100, 100 m2 and over is considered "large". This is for cities and towns, in the country 60 m2 would probably be considered "tiny".