How do you calculate sheet metal weight?

We commonly speak of weight in kilograms, but this calculation gives mass. For a solid rectangular sheet: mass (kg) = length (m) × width (m) × thickness (m) × density (kg/m³).

If all dimensions are in millimetres: mass (kg) = length × width × thickness × density ÷ 1 000 000 000. The conversion applies to volume, so all three dimensions are involved.

These values are estimates. Exact density depends on the grade; use the supplier’s material datasheet when accuracy matters.

A 1 500 × 3 000 × 2 mm steel sheet converts to 1.5 × 3 × 0.002 m. Its volume is 0.009 m³, giving a theoretical mass of 0.009 × 7 850 = 70.65 kg.

At identical dimensions, the estimate is 72 kg for stainless steel at 8 000 kg/m³ and 24.3 kg for aluminium at 2 700 kg/m³. This compares mass, not the mechanical equivalence of the parts.

For a cut part, use the net area: outer area minus holes and cut-outs. Multiply this by thickness and density.

Example: a 500 × 300 × 3 mm steel plate with a 100 × 100 mm rectangular opening has a net area of 0.15 − 0.01 = 0.14 m². Its mass is 0.14 × 0.003 × 7 850 = 3.297 kg, approximately 3.30 kg.

Net mass is not necessarily the mass billed. Gaps between parts, sheet margins and offcuts affect actual consumption. For a batch, distinguish delivered part weight from the weight of sheets required.

Actual mass also varies with thickness tolerances, dimensions and coatings. Add packaging and accessories for transport; the geometric calculation does not include them.

The Sheet prices & weights tool compares materials, formats and thicknesses. Check units and the selected grade before using the result in your estimate.