10 Gauge Sheet Metal

Steel (MSG) 0.1345″
Galvanized 0.1382″
Stainless 0.1406″
Aluminum 0.1019″

Steel: 3.42 mm · Galvanized: 3.51 mm · Stainless: 3.57 mm · Aluminum: 2.59 mm . The same gauge number is a different thickness in each material — always confirm which scale a drawing means, or better, specify decimal thickness.

Neighboring gauges (steel column)

Gauge Steel Galvanized Stainless Aluminum
8 0.1644 0.1681 0.1719 0.1285
9 0.1495 0.1532 0.1562 0.1144
10 0.1345 0.1382 0.1406 0.1019
11 0.1196 0.1233 0.1250 0.0907
12 0.1046 0.1084 0.1094 0.0808

Measuring wire, not sheet? Wire uses the AWG scale — see AWG 10 (0.1019″ Ø). Aluminum sheet happens to share the AWG scale, which is why the aluminum column matches it.

Data provenance. Sheet-metal gauge tables: Manufacturers’ Standard Gauge (steel), galvanized, and stainless (Industry reference). ASTM B258, Standard Specification for Nominal Diameters of AWG Sizes (ASTM International). Steel per Manufacturers' Standard Gauge; stainless per the conventional supplier table (no governing standard); aluminum per B&S (= AWG, ASTM B258). Sheets carry rolling tolerances. See all data sources.