← Back to Bead BoardMetal weight calculator
Plate, pipe, bar, tube. Every common steel, stainless, aluminum, and brass spec. One sheet or a thousand. Imperial and metric, switching on the fly, with the density shown so you can check the math.
Weights are calculated from published densities and standard section geometry. Real plate and bar stock runs ±2–3% from spec.
Shape-specific calculators
Quoting a specific material and shape combo comes up a lot more than the generic version. We keep a separate page for each so it is one click from Google to the answer.
Steel Plate Weight
A36 mild steel. Every thickness from 1/16 up.
Steel Pipe Weight
NPS 1/2 through 8, Schedule 40/80/XXS.
Steel Round Bar Weight
1018, A36, hot-rolled round stock.
Steel Square Tube (HSS)
Hollow structural section by size and wall.
Aluminum Plate Weight
6061-T6 and 5052 plate.
Stainless Plate Weight
304 and 316 plate in lb or kg.
The densities behind the math
Sources: MatWeb, AK Steel datasheets, Copper.org, AmesWeb. Real stock varies 2–3% from these numbers due to mill tolerances and alloy composition.
Questions welders keep asking
How do you calculate the weight of a metal part?
Multiply volume by density. Volume depends on the shape. Plate is length × width × thickness. Round bar is π × r² × length. Tube is the outer area minus the inner area times length. Density depends on the alloy. Mild steel is 0.2836 lb/in³, 6061 aluminum is 0.0975, 304 stainless is 0.289, brass is 0.307.
What is the density of mild steel in lb/in³?
0.2836 lb/in³ (7.85 g/cm³) for A36 mild steel. This is the number behind every "lb per foot" chart you will find for plate, pipe, and bar. Stainless is slightly denser at 0.289, tool steel is in the same range, and aluminum is about a third at 0.0975.
How much does a 4×8 sheet of 1/4 inch mild steel weigh?
About 327 pounds. Math: 48 × 96 × 0.25 × 0.2836 = 326.7 lb. The same sheet in 6061 aluminum is 112 lb. In 304 stainless it is 333 lb. 316 stainless is the same 333 lb because the density is identical.
How much does 1 foot of 2 inch Schedule 40 steel pipe weigh?
About 3.65 lb per foot. Math: OD 2.375, wall 0.154, so ID = 2.067. Cross-section area = π/4 × (2.375² − 2.067²) = 1.07 in². Volume per foot = 12.9 in³. Weight = 12.9 × 0.2836 = 3.66 lb/ft. Published ASME B36.10 tables list 3.65 lb/ft. The 0.3% difference is rounding.
Does real stock match the calculated weight?
Within about 2–3%. Mill tolerances, scale, and slight variations in alloy composition mean the actual weight of a 4×8 plate might be 320 lb or 335 lb, not exactly 327. For quoting material cost, the calculated number is plenty accurate. For bearing load calculations, use the actual supplier certification.
Imperial or metric: does it matter?
No. The calculator handles both and shows results in both units. Imperial uses inches and pounds. Metric uses millimeters and kilograms. Pipe sizes stay in NPS (Nominal Pipe Size) even on metric projects because that is how the industry actually buys pipe.