What is the steel weight?
Pick the shape, type its size and length, and choose carbon or stainless steel. The steel weight calculator gives the weight of one piece, the total, and the weight per foot and per metre.
- Total weight
- 326.667 lb
The steel weighs 326.667 lb in all (40.833 lb per foot).
- Weight of one piece
- 326.667 lb
- Weight per footlb/ft
- 40.833
- Weight per metrekg/m
- 60.767
- Cross-section areain²
- 12
Total weight: 326.667 lb. The steel weighs 326.667 lb in all (40.833 lb per foot).
How to calculate
Computes the weight of steel plate, flat bar, round and square bar, pipe, tube and angle from its size and length, with the weight per foot and per metre, for carbon or stainless steel.
Example with the default inputs (Shape Plate, sheet or flat bar, Width 48 in, Thickness 0.25 in, Length 8 ft, Pieces 1, Material Carbon steel, 490 lb/ft³): The steel weighs 326.667 lb in all (40.833 lb per foot).
Method: Weight = density × cross-section area × length × pieces. Areas: plate w × t; round bar π ÷ 4 × d²; square bar a²; pipe π ÷ 4 × (D² − (D − 2t)²); tube w × h − (w − 2t)(h − 2t); angle t × (a + b − t).
- Corners are sharp: the rounded corners of tubes and angles and the radii of rolled shapes are left out, so real weights can be slightly lower.
- Densities: 490 lb/ft³ (0.2836 lb/in³) or 7,850 kg/m³ for carbon steel, 8,000 kg/m³ for 304 stainless; or type your own.
Worked examples
Each example is checked against the calculator on every build.
- Shape Plate, sheet or flat bar, Width 48 in, Thickness 0.25 in, Length 8 ft, Pieces 1, Material Carbon steel, 490 lb/ft³ gives Total weight 326.667 lb, Weight per foot 40.833333.Source: ASTM A992 structural steel, density 0.2836 lb/in³ (490 lb/ft³), Wikipedia (https://en.wikipedia.org/wiki/ASTM_A992, retrieved 2026-10-01)
- Shape Round tube or pipe, Diameter 2.375 in, Thickness 0.154 in, Length 20 ft, Pieces 1, Material Carbon steel, 490 lb/ft³ gives Weight per foot 3.656392, Weight of one piece 73.1278 lb.Source: ASME B36.10M, 2 in schedule 40 pipe: 2.375 in OD, 0.154 in wall, 3.66 lb/ft, as tabulated at https://metalsrus.ca/blogs/guides/pipe-schedule-chart (retrieved 2026-10-01)
- Shape Round bar, Diameter 0.7874 in, Length 19.69 ft, Pieces 10, Material Carbon steel, 7,850 kg/m³ gives Total weight 326.216 lb, Weight per metre 2.46615.Source: EN 1991-1-1 Table A.4, structural steel 77.0 to 78.5 kN/m³, used as 7,850 kg/m³ (https://eurocodeapplied.com/design/en1993/steel-design-properties, retrieved 2026-10-01)
- Shape Angle, Width 1.969 in, Height 1.969 in, Thickness 0.1969 in, Length 3.281 ft, Pieces 1, Material Stainless steel 304, 8,000 kg/m³ gives Total weight 8.37757 lb.Source: Thyssenkrupp Materials (UK), stainless steel 304 / 1.4301 data sheet, density 8,000 kg/m³ (https://www.thyssenkrupp-materials.co.uk/stainless-steel-304-14301.html, retrieved 2026-10-01)
How it works
Weight of one piece = density × cross-section area × length. Total weight = one piece × pieces.
The cross-section area A for each shape, with sharp corners:
- Plate, sheet or flat bar: A = width × thickness.
- Round bar: A = π ÷ 4 × diameter².
- Square bar: A = side².
- Round tube or pipe: A = π ÷ 4 × (D² − (D − 2t)²), with D the outside diameter and t the wall.
- Square or rectangular tube: A = w × h − (w − 2t) × (h − 2t).
- Angle: A = t × (a + b − t), with legs a and b and thickness t.
The calculator also shows:
- Weight per foot = density × A × 0.3048 m, in pounds (÷ 0.45359237), to 5 significant figures.
- Weight per metre = density × A, in kilograms, to 5 significant figures.
- Cross-section area in square inches (A ÷ 0.0254²), to 6 significant figures.
The weights show to 6 significant figures, in pounds (US) or kilograms (Metric). The maths runs in floating point and every value is rounded half up for display only.
Densities. Carbon steel 490 lb/ft³ (7,849.05 kg/m³; 0.2836 lb/in³), carbon steel 7,850 kg/m³ (the metric design value), 304 stainless steel 8,000 kg/m³, or a density you type (100 to 25,000 kg/m³).
Rules
- Sizes are from 0.1 mm to 10 m; the length from 0.1 mm to 1,000 m; pieces from 1 to 100,000. 1 in = 25.4 mm and 1 ft = 0.3048 m exactly.
- A tube or pipe whose wall is half its outside size or more (the smaller side for a rectangular tube) has no answer: "The wall is at least half the outside size, so the tube would be solid."
- An angle whose thickness is at least its shorter leg has no answer: "The thickness is at least the width of a leg."
Worked examples by hand
A 4 × 8 ft sheet of 1/4 in plate. A = 48 × 0.25 = 12 in²; volume = 12 × 96 = 1,152 in³ = 0.66667 ft³; weight = 0.66667 × 490 = 326.67 lb (148.17 kg). Per foot: 12 ÷ 144 × 490 = 40.833 lb.
20 ft of 2 in schedule 40 pipe. ID = 2.375 − 2 × 0.154 = 2.067 in. A = π ÷ 4 × (2.375² − 2.067²) = 1.0745 in². Per foot: 1.0745 ÷ 144 × 490 = 3.6564 lb; 20 ft = 73.13 lb.
Ten 6 m round bars, 20 mm. A = π ÷ 4 × 0.02² = 0.00031416 m²; per metre 0.00031416 × 7,850 = 2.4662 kg; total 2.4662 × 6 × 10 = 147.97 kg.
A 1 m stainless angle, 50 × 50 × 5 mm. A = 5 × (50 + 50 − 5) = 475 mm² = 0.000475 m²; weight = 0.000475 × 1 × 8,000 = 3.8 kg.
Other questions people ask
How do I calculate the weight of steel?
Multiply the cross-section area by the length to get the volume, then by the density. A 4 × 8 ft sheet of 1/4 in plate is 48 × 96 × 0.25 = 1,152 in³ = 0.6667 ft³, and at 490 lb/ft³ it weighs 326.67 lb.
What is the density of steel?
Carbon and structural steel is about 490 lb/ft³ (0.2836 lb/in³), or 7,850 kg/m³ in metric design (EN 1991-1-1 gives 77.0 to 78.5 kN/m³). 304 stainless steel is about 8,000 kg/m³.
How much does steel plate weigh per square foot?
About 40.8 lb per square foot for each inch of thickness: 1/4 in plate is about 10.2 lb/ft², 1/2 in about 20.4 lb/ft².
How do I find the weight of steel pipe?
Use the ring area: π ÷ 4 × (OD² − ID²), where ID = OD − 2 × wall. 2 in schedule 40 pipe (2.375 in OD, 0.154 in wall) has 1.0745 in² of steel and weighs 3.66 lb per foot, matching the 3.66 lb/ft in the Metals R Us pipe chart.
What is the weight of a round steel bar?
π ÷ 4 × diameter² × length × density. A 20 mm bar weighs π ÷ 4 × 0.02² × 7,850 = 2.47 kg per metre.
Why is my supplier’s weight a little lower?
Tubes and angles have rounded corners, and rolled sections have radii. The calculator uses sharp corners, which adds a little steel. Supplier tables also use their own density and rounding.