Sheet Metal Weight Calculator: Plate Mass in kg & lb

Published September 22, 2026 · MfgWorkbench editorial reference

Estimate the mass of rectangular sheet stock using a material density you choose. Enter physical thickness in millimeters, not a gauge number.

Mass formula and units

Mass in kg = length(mm) × width(mm) × thickness(mm) × density(kg/m³) / 1,000,000,000. The divisor converts cubic millimeters to cubic meters. Pounds = kilograms × 2.20462262185. Quantity multiplies mass per sheet; it does not change any geometry.

The default density of 7,850 kg/m³ is a planning value for carbon steel, not a certified value for every grade. Aluminum alloys, stainless grades and other metals need their own density. Use the material datasheet where weight affects a design, shipping limit or purchasing commitment.

Example: a 2 m × 1 m × 2 mm steel sheet

Entering 2000 mm, 1000 mm, 2 mm and 7850 kg/m³ gives 31.4 kg, approximately 69.2252 lb, per sheet. Ten identical sheets total 314 kg before packaging. An otherwise identical sheet with density 2700 kg/m³ would be 10.8 kg.

For a rectangular cutout, calculate its mass with the same thickness and density and subtract it from the gross blank mass. Complex nests, perforated material and folded assemblies require actual net area or CAD mass properties; this calculator intentionally models a solid rectangle.

Gross stock versus finished-part mass

A bounding rectangle usually overstates the mass of a profiled part. Coatings, fasteners, weld metal and packaging are not included. Actual thickness and alloy density vary, so an estimate may differ from a scale reading.

For a batch quote, distinguish purchased sheet mass from net finished mass. Material utilization affects cost even though it does not change the density. For handling or lifting, use verified actual mass and the applicable equipment procedure; this planning estimate is not a lifting plan.