TFT

Steel Weight Calculator – Calculate Weight of Steel Sections and Bars

Find the weight of any steel component quickly. Our steel weight calculator covers bars, plates, pipes, and structural sections in kg or lbs from standard dimensions.

Material Densities Reference
Common metal densities for weight calculations
MaterialDensity (kg/m³)Density (lb/in³)Relative Weight
Aluminum2,7000.09734% of steel
Titanium4,5000.16357% of steel
Cast Iron7,2000.26092% of steel
Mild Steel7,8500.284Baseline
Stainless Steel8,0000.289102% of steel
Brass8,5000.307108% of steel
Copper8,9600.324114% of steel

Densities vary slightly by alloy composition. Values shown are typical averages for common grades.

Steel Weight Formulas
How to calculate weight manually

Weight = Volume × Density. The volume calculation changes based on shape, but the principle stays the same. For steel, use 7850 kg/m³ or 0.284 lb/in³ as your density.

Volume Formulas (all dimensions in meters):

Round Bar: π × (diameter/2)² × length

Sheet/Plate: length × width × thickness

Pipe/Tube: π × ((OD/2)² - (ID/2)²) × length

Flat Bar: width × thickness × length

For pipes, you can also use wall thickness instead of inner diameter: Volume = π × (OD - wall) × wall × length. This is often easier when you have standard pipe schedules.

Common Steel Section Weights
Reference weights for standard sizes
Section TypeSizeWeight per MeterWeight per Foot
Round Bar20mm diameter2.47 kg/m1.66 lb/ft
Round Bar25mm diameter3.85 kg/m2.59 lb/ft
Steel Plate10mm thick78.5 kg/m²16.1 lb/ft²
Steel Plate20mm thick157 kg/m²32.2 lb/ft²
Steel Pipe2" SCH 405.44 kg/m3.66 lb/ft
Steel Pipe4" SCH 4016.07 kg/m10.8 lb/ft

Weights are theoretical and may vary slightly from actual due to manufacturing tolerances.

Frequently Asked Questions

What is the density of mild steel?

Mild steel (low carbon steel) has a density of approximately 7850 kg/m³ or 7.85 g/cm³. In imperial units, that's 0.284 lb/in³ or 490 lb/ft³. This is the standard value used for most structural steel calculations.

How do I calculate the weight of a steel pipe?

For a pipe, calculate the cross-sectional area of the steel ring: π × ((OD/2)² - (ID/2)²), then multiply by length for volume, then by density for weight. Or use the shortcut: Weight/m = (OD - wall) × wall × 0.02466 for mm dimensions in kg/m.

Is stainless steel heavier than regular steel?

Slightly. Stainless steel (typically 8000 kg/m³) is about 2% denser than mild steel (7850 kg/m³). The difference comes from alloying elements like chromium and nickel. For most practical purposes, you can treat them as having the same density.

How much does a 4x8 sheet of steel weigh?

Depends on thickness. A 4×8 foot sheet of 1/4" steel weighs about 327 lbs. At 1/2" thick, it's 654 lbs. At 1" thick, roughly 1300 lbs. The formula: length(ft) × width(ft) × thickness(in) × 40.8 = weight in pounds.

Why is aluminum so much lighter than steel?

Aluminum's density (2700 kg/m³) is only 34% of steel's. This is due to aluminum's atomic structure – lighter atoms packed less densely. That's why aluminum is popular in aerospace and automotive applications where weight matters.