Sheet metal gauge chart: gauge to mm for steel, galvanized, stainless and aluminium, with sheet weights
Gauge to mm conversion for steel, galvanized steel, stainless steel, aluminium and UK SWG, sheet and plate weight per m² from 0.5 to 20 mm, and the weight of 1000×2000, 1250×2500 and 1500×3000 sheets.
Updated October 17, 2026
Sheet metal in the US and UK is often specified by gauge, while mills and European buyers order in millimetres. The gauge number does not convert to one thickness: it means a different thickness for steel, galvanized steel, stainless steel and aluminium. This guide converts gauge to mm for each material and gives the weight of sheet per square metre and per standard sheet.
Sheet metal gauge to mm chart
| Gauge | Steel (mm) | Galvanized steel (mm) | Stainless steel (mm) | Aluminium (mm) | SWG, UK (mm) |
|---|---|---|---|---|---|
| 8 | 4.18 | 4.27 | 4.37 | 3.26 | 4.06 |
| 10 | 3.42 | 3.51 | 3.57 | 2.59 | 3.25 |
| 11 | 3.04 | 3.13 | 3.17 | 2.30 | 2.95 |
| 12 | 2.66 | 2.75 | 2.78 | 2.05 | 2.64 |
| 13 | 2.28 | 2.37 | 2.38 | 1.83 | 2.34 |
| 14 | 1.90 | 1.99 | 1.98 | 1.63 | 2.03 |
| 15 | 1.71 | 1.80 | 1.79 | 1.45 | 1.83 |
| 16 | 1.52 | 1.61 | 1.59 | 1.29 | 1.63 |
| 17 | 1.37 | 1.46 | 1.43 | 1.15 | 1.42 |
| 18 | 1.21 | 1.31 | 1.27 | 1.02 | 1.22 |
| 19 | 1.06 | 1.16 | 1.11 | 0.91 | 1.02 |
| 20 | 0.91 | 1.01 | 0.95 | 0.81 | 0.91 |
| 21 | 0.84 | 0.93 | 0.87 | 0.72 | 0.81 |
| 22 | 0.76 | 0.85 | 0.79 | 0.64 | 0.71 |
| 23 | 0.68 | 0.78 | 0.71 | 0.57 | 0.61 |
| 24 | 0.61 | 0.70 | 0.64 | 0.51 | 0.56 |
| 25 | 0.53 | 0.63 | 0.56 | 0.45 | 0.51 |
| 26 | 0.45 | 0.55 | 0.48 | 0.40 | 0.46 |
| 28 | 0.38 | 0.47 | 0.40 | 0.32 | 0.38 |
| 30 | 0.30 | 0.40 | 0.32 | 0.25 | 0.32 |
- Steel — Manufacturers' Standard Gauge for uncoated carbon steel sheet.
- Galvanized steel — galvanized sheet gauge, which includes the zinc coating and so is slightly thicker than steel of the same gauge.
- Stainless steel — the US gauge commonly used for stainless sheet.
- Aluminium — Brown & Sharpe (AWG) gauge, used for aluminium and other non-ferrous sheet.
- SWG — British Standard Wire Gauge, still used for sheet in the UK and some Commonwealth markets.
Sheet and plate weight per square metre
Sheet weight is thickness (mm) × density = kg/m². With densities of 7.85 kg/dm³ for carbon steel, 7.93 for 304 stainless steel and 2.70 for aluminium, a 2 mm steel sheet weighs 2 × 7.85 = 15.7 kg/m².
| Thickness (mm) | Steel (kg/m²) | Stainless 304 (kg/m²) | Aluminium (kg/m²) |
|---|---|---|---|
| 0.5 | 3.92 | 3.96 | 1.35 |
| 0.6 | 4.71 | 4.76 | 1.62 |
| 0.8 | 6.28 | 6.34 | 2.16 |
| 1 | 7.85 | 7.93 | 2.70 |
| 1.2 | 9.42 | 9.52 | 3.24 |
| 1.5 | 11.77 | 11.89 | 4.05 |
| 2 | 15.70 | 15.86 | 5.40 |
| 2.5 | 19.62 | 19.82 | 6.75 |
| 3 | 23.55 | 23.79 | 8.10 |
| 4 | 31.40 | 31.72 | 10.80 |
| 5 | 39.25 | 39.65 | 13.50 |
| 6 | 47.10 | 47.58 | 16.20 |
| 8 | 62.80 | 63.44 | 21.60 |
| 10 | 78.50 | 79.30 | 27.00 |
| 12 | 94.20 | 95.16 | 32.40 |
| 15 | 117.75 | 118.95 | 40.50 |
| 20 | 157.00 | 158.60 | 54.00 |
Weight of a standard steel sheet
| Thickness (mm) | 1000 × 2000 | 1250 × 2500 | 1500 × 3000 |
|---|---|---|---|
| 0.5 | 7.8 | 12.3 | 17.7 |
| 0.6 | 9.4 | 14.7 | 21.2 |
| 0.8 | 12.6 | 19.6 | 28.3 |
| 1 | 15.7 | 24.5 | 35.3 |
| 1.2 | 18.8 | 29.4 | 42.4 |
| 1.5 | 23.5 | 36.8 | 53.0 |
| 2 | 31.4 | 49.1 | 70.6 |
| 2.5 | 39.2 | 61.3 | 88.3 |
| 3 | 47.1 | 73.6 | 106.0 |
| 4 | 62.8 | 98.1 | 141.3 |
| 5 | 78.5 | 122.7 | 176.6 |
| 6 | 94.2 | 147.2 | 211.9 |
| 8 | 125.6 | 196.2 | 282.6 |
| 10 | 157.0 | 245.3 | 353.2 |
| 12 | 188.4 | 294.4 | 423.9 |
| 15 | 235.5 | 368.0 | 529.9 |
| 20 | 314.0 | 490.6 | 706.5 |
For stainless steel multiply the steel value by about 1.01; for aluminium divide it by about 2.9. For other sizes and shapes use the weight calculator.
Sheet we supply
- [Hot-rolled sheet and plate](/steel-sheet-hr) — S235JR, 1.5 to 20 mm.
- [Cold-rolled sheet (DKP)](/steel-sheet-dkp) — DC01, 0.5 to 2 mm, for bending and painted parts.
- [Galvanized sheet](/steel-sheet-galvanized) — DX51D+Z, 0.5 to 2 mm.
- [Checker plate](/steel-sheet-checker) — S235JR, 3 to 10 mm base thickness; the raised pattern adds weight above the plain-plate value.
- [Stainless steel sheet](/stainless-steel-sheet-304) — AISI 304, 0.8 to 8 mm, 2B finish.
- Aluminium sheet — 1050 H14 and 5754, 1 to 3 mm.
Standard sheet sizes are 1000 × 2000, 1250 × 2500 and 1500 × 3000 mm. Sheet can also be supplied cut to your drawings through our laser cutting service.
Frequently asked questions
How thick is 16 gauge steel in mm?
16 gauge carbon steel is 1.52 mm (0.0598 in). 16 gauge galvanized steel is 1.61 mm, 16 gauge stainless steel 1.59 mm and 16 gauge aluminium 1.29 mm.
How thick is 18 gauge sheet metal?
18 gauge carbon steel is 1.21 mm, galvanized 1.31 mm, stainless steel 1.27 mm and aluminium 1.02 mm. In the nearest metric thicknesses this is usually ordered as 1.2 mm steel or 1 mm aluminium.
Is a higher gauge number thicker or thinner?
Thinner. Gauge numbers run backwards: 10 gauge steel is 3.42 mm, while 20 gauge is 0.91 mm.
How much does a 1250 × 2500 steel sheet weigh?
Multiply the area, 3.125 m², by the weight per m². A 2 mm steel sheet weighs 15.7 kg/m², so a 1250 × 2500 sheet weighs about 49.1 kg; a 3 mm sheet about 73.6 kg.
Send your sheet list with thickness, grade, size and quantity in a quote request.
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