Rectangular Tube Weight Calculator

Find square or rectangular tube weight from dimensions.

Unit system

Inputs

mm
mm
mm
m
kg/m³

Nominal densities; choose custom density to enter your own.

pcs

Results

Total weight

3.49kg
Equivalent values7.68 lb
Weight per unit length
3.49 kg/m2.34 lb/ft
Weight per piece
3.49 kg7.68 lb
Metal cross-sectional area
444 mm²
Metal volume per piece
0.000444 m³
Inner width
44 mm
Inner height
24 mm

This is a sharp-corner theoretical model. Real structural tubes can have inner and outer corner radii, so manufacturer standard weights may differ. Nominal density, wall tolerances, welds and coatings also affect mass.

Formula · How it works

Formula

Wᵢ = W − 2t; Hᵢ = H − 2t; A = WH − WᵢHᵢ; V = A × L; m = V × ρ; mₜ = m × q

Inner width Wᵢ = W − 2t and inner height Hᵢ = H − 2t. Metal area A = WH − WᵢHᵢ = 2t(W + H − 2t). Volume per piece V = A × L; mass per piece = V × ρ; total mass = mass per piece × quantity.

Worked example

A 50 × 30 mm rectangular tube with a 3 mm wall has inner dimensions 44 × 24 mm and metal area 444 mm². At 7,850 kg/m³, it weighs 3.4854 kg per metre. Two 2 m pieces weigh 13.9416 kg.

How it works

The model subtracts a centred rectangular opening from the outer rectangle and assumes a uniform wall thickness. Entering equal outer dimensions produces a square section. Volume refers to the material in one piece.

Common questions

How do I calculate square tube weight?

Enter the same value for outer width and outer height. The wall thickness, length, material and quantity work the same way as for rectangular tube.

Why does the result differ from a supplier's table?

The model assumes sharp corners and exact, uniform wall thickness. Real tubes have corner radii and dimensional tolerances, and their alloy density can differ from the nominal preset. Use the manufacturer's section data when selecting a product.