← 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.
Quick answer
Metal weight is volume times density. A36 mild steel is 0.2836 lb/in³, 304 stainless is 0.289 lb/in³, and 6061 aluminum is 0.0975 lb/in³. A 4×8 sheet of 1/4-inch A36 plate weighs about 327 lb.
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 Flat Bar Weight
A36 flat bar by width and thickness.
Steel Angle (Angle Iron)
Equal-leg angle by leg and thickness.
Steel Square Tube (HSS)
Hollow structural section by size and wall.
Steel Rectangular Tube (HSS)
Rectangular HSS by width, height, and wall.
Steel Round Tube Weight
DOM and ERW mechanical tubing by OD and wall.
Aluminum Plate Weight
6061-T6 and 5052 plate.
Aluminum Round Bar Weight
6061-T6 round bar by diameter and length.
Stainless Plate Weight
304 and 316 plate in lb or kg.
Stainless Round Bar Weight
304/316 stainless round bar by diameter.
Sheet Metal Gauge Chart
Gauge to thickness for steel, stainless, aluminum.
Plate Weight Chart
Weight per square foot by thickness. Steel, stainless, aluminum.
Pipe Weight Chart
Weight per foot by NPS and schedule. Sch 40, 80, XXS.
Metal weight comparison — same part, different materials
Side-by-side weight for the same dimensions across the materials shops use most. All numbers are a 4×8 sheet (48" × 96") at the given thickness.
Aluminum is about 34% the weight of steel for the same dimensions. Stainless and brass are slightly heavier than mild steel. These numbers use the exact densities in the calculator above.
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 A36 steel weigh?
A36 mild steel weighs 0.2836 lb per cubic inch, or 490 lb per cubic foot, or 7.85 g/cm³. It is the same density as 1018, 1020, and most hot-rolled and cold-rolled carbon steels. To get the weight of a specific part, multiply the volume (in cubic inches) by 0.2836.
What is the weight of mild steel per cubic inch?
0.2836 lb/in³. Mild steel covers A36, 1018, 1020, and other low-carbon steels — they all use the same density for weight calculations. In metric, that is 7.85 g/cm³. The density of stainless steel is slightly higher at 0.289 lb/in³ (8.00 g/cm³).
What is the weight of stainless steel per cubic inch?
0.289 lb/in³ (8.00 g/cm³) for 304 and 316 stainless steel. That is about 2% denser than mild steel at 0.2836 lb/in³. The nickel content (8–14%) in austenitic stainless is what makes it slightly heavier than carbon steel.
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 within 1% of the same number.
How much does a 4×8 sheet of 3/8 inch steel plate weigh?
About 490 pounds. Math: 48 × 96 × 0.375 × 0.2836 = 490.1 lb. That is 50% more than a 1/4 inch sheet (327 lb) because you are adding 50% more thickness. Real plate from the mill will be ±2–3% of that.
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.
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