How to Calculate Aluminium Weight: Formula, Density and Worked Examples
Aluminium weighs roughly one third as much as steel, and that is exactly why it is specified for frames, façades, transport and machinery. But when you quote, order or ship profiles you need the actual number. This guide shows how to calculate aluminium weight from dimensions, which density to use, and gives worked examples for the most common shapes.
The basic formula
Weight is volume multiplied by density:
Weight (kg) = Volume (m³) × Density (kg/m³)
For most aluminium alloys the density is about 2,700 kg/m³ (2.70 g/cm³). For profiles it is easier to work from the cross-sectional area, because the weight per metre then follows directly:
Weight per metre (kg/m) = Cross-section area (mm²) × 0.0027
Multiply the result by the length in metres to get the weight of one piece, and by the quantity for the total.
Which density should you use?
Alloys differ slightly. These are the values used in the EAS weight calculator:
| Alloy | Density (g/cm³) |
|---|---|
| 6060, 6061, 6063, 6082, 6005, 5005 | 2.70 |
| 1050, 1100 | 2.71 |
| 3003 | 2.73 |
| 5052 | 2.68 |
| 5754, 5083 | 2.66 |
| 2024 | 2.78 |
| 7075 | 2.81 |
The kg/m values in the EAS standard profile catalogue are calculated with 2.70. For extruded 6xxx-series profiles the difference between alloys is under one percent, so 2.70 is the normal choice.
Worked examples (alloy 6063, 2.70 g/cm³)
| Shape | Dimensions | Cross-section | Weight per metre |
|---|---|---|---|
| Flat bar | 50 × 5 mm | 50 × 5 = 250 mm² | 0.675 kg/m |
| Round bar | Ø 20 mm | π × 10² ≈ 314.2 mm² | 0.848 kg/m |
| Square tube | 40 × 40 × 2 mm | 40² − 36² = 304 mm² | 0.821 kg/m |
| Rectangular tube | 60 × 30 × 2 mm | 60×30 − 56×26 = 344 mm² | 0.929 kg/m |
| Round tube | Ø 30 × 2 mm | π/4 × (30² − 26²) ≈ 175.9 mm² | 0.475 kg/m |
| Equal angle | 40 × 40 × 4 mm | 40×4 + 36×4 = 304 mm² | 0.821 kg/m |
One piece: a 6 m length of the 40 × 40 × 2 mm square tube weighs 0.821 × 6 ≈ 4.93 kg.
Why a calculated weight is only theoretical
These figures assume sharp corners and nominal dimensions. A real extruded profile has corner radii and a wall thickness within tolerance, so its actual weight can differ slightly from the theoretical value. For complex profiles with several chambers or ribs, hand calculation becomes impractical; use the cross-section area from the technical drawing or the kg/m value published in the catalogue.
Calculate it automatically
Instead of working through the geometry by hand, use the EAS aluminium weight calculator. Pick the shape (square tube, rectangular tube, round bar, flat bar, angle and more), enter the dimensions and length, choose the alloy, and it returns the weight per metre, per piece and in total. You can also look up a standard profile by its number in the online catalogue.
Frequently asked questions
How much does aluminium weigh per cubic metre?
About 2,700 kg per cubic metre for the common 6xxx alloys (2.70 g/cm³).
How do I calculate the weight of an aluminium profile per metre?
Multiply the cross-section area in mm² by 0.0027. A profile with 304 mm² cross-section weighs about 0.82 kg per metre.
Is aluminium really a third of the weight of steel?
Yes. Steel is about 7.85 g/cm³, aluminium about 2.70 g/cm³, so aluminium is roughly 34% of the weight for the same volume.
Need a weight or a quotation for a specific profile? Contact the EAS team with your drawing or profile number.
