The thickness of standard 10 gauge steel is 0.1345 inches. The gauge numbers of alloys such as steel refer to the thickness of a sheet piece. However, the gauge number for steel also can vary depending on its specific type, such as galvanized or stainless steel.
For example, the thickness for 10 gauge galvanized steel is 0.1382 inches, and for stainless steel it is 0.1406 inches. When looking at the thicknesses of steel sheets, it is evident that increasing gauge numbers are associated with smaller sheet thicknesses.
Standard 30 gauge steel has a thickness of 0.0120 inches. Standard steel gauge numbers can range from 3 to 38. These thickness gauges, which are referred to generally as the Manufacturers' Standard Gauge for sheet steel, are primarily used in the United States.