Aluminium is about one third the weight of steel, which is why it is used for boats, trailers, ladders and window frames. Different alloys vary slightly in density – 7075 is about 4% heavier than 5052 – so this calculator lets you pick the alloy as well as the shape and size of the stock.
How to use the Aluminum Weight Calculator
- Alloy
- Custom density
- Shape
- Width / diameter / side / leg
- Height (rectangular tube)
- Thickness / wall
- Sheet area
- Length
- Number of pieces
- Every result field is editable: type into Weight of one piece or any other result and Length plus every other field update to match.
Results update as you type, and every field accepts the units shown in its menu.
How it works
The calculator works out the cross-sectional area of the shape you choose, multiplies it by the length to get the volume, then by the density of the material to get the weight. Tubes subtract the hollow core; angles count both legs once.
Densities used
| Alloy | kg/m³ | lb/in³ | lb/ft³ |
|---|---|---|---|
| Aluminium (average) | 2,700 | 0.0975 | 168.6 |
| 1100 | 2,710 | 0.0979 | 169.2 |
| 2024 | 2,780 | 0.1004 | 173.5 |
| 3003 | 2,730 | 0.0986 | 170.4 |
| 5052 | 2,680 | 0.0968 | 167.3 |
| 5083 | 2,660 | 0.0961 | 166.1 |
| 6061 | 2,700 | 0.0975 | 168.6 |
| 6063 | 2,690 | 0.0972 | 167.9 |
| 6082 | 2,700 | 0.0975 | 168.6 |
| 7075 | 2,810 | 0.1015 | 175.4 |
Tips for an accurate estimate
- Sketch the job and split irregular areas into rectangles, circles and triangles before you measure.
- Add a waste allowance – typically 5–10% for simple layouts and 15–20% for diagonal, curved or heavily cut work.
- Check the coverage or yield printed on the product, because sizes and densities vary between manufacturers.
- Buy all units of a finished material (tile, brick, siding) from the same batch so colours match, and keep a few spares for repairs.
- Confirm local prices – quarry, lumber and steel prices vary widely by region and season.
Common mistakes to avoid
- Ordering exactly the calculated amount with no allowance for breakage, offcuts and settlement.
- Forgetting to subtract doors, windows and other openings – or subtracting small ones that still need cutting around.
- Confusing US short tons (2,000 lb) with metric tonnes (1,000 kg) when comparing quotes.
Inputs explained
| Field | What to enter |
|---|---|
| Alloy | Choose one: Aluminium (average), 1100, 2024, 3003 … |
| Custom density | Units: kg/m³, lb/ft³, g/cm³, lb/yd³ |
| Shape | Choose one: Plate / flat bar (width × thickness), Round bar (diameter), Square bar (side), Hexagonal bar (across flats) … |
| Width / diameter / side / leg | Units: mm, in, cm |
| Height (rectangular tube) | Units: mm, in, cm |
| Thickness / wall | Units: mm, in, cm |
| Sheet area | Units: m², ft², yd² |
| Length | Units: m, ft, cm, in, yd |
| Number of pieces | A number |
Formula
Weight = cross-section area × length × density × piecesTube area = π/4 × (D² − (D − 2t)²)Angle area = t × (2a − t)Worked example
Inputs — Alloy: Aluminium (average); Custom density: 7,850 kg/m³; Shape: Plate / flat bar (width × thickness); Width / diameter / side / leg: 1,219.2 mm; Height (rectangular tube): 50 mm; Thickness / wall: 3.175 mm; Sheet area: 1 m²; Length: 2.4384 m; Number of pieces: 1.
Results — Cross-section area = 3,870.96 mm²; Volume of one piece = 9,438.949 cm³; Weight of one piece = 25.485 kg; Total weight = 25.485 kg; Weight per metre = 10.452 kg/m.
Frequently asked questions
How much does aluminium weigh?
About 2,700 kg/m³, or 0.0975 lb/in³ (168.5 lb/ft³).
How much does a sheet of aluminium weigh?
A 4 × 8 ft sheet ⅛ in thick weighs about 56 lb (25 kg).
Is aluminium lighter than steel?
Yes, roughly 35% of the weight of steel for the same volume.
What formula does the Aluminum Weight Calculator use?
Weight = cross-section area × length × density × pieces.