Steel & metal weight calculator
Pick the metal and the shape, enter the sizes in millimetres, and get the weight of one piece, the whole lot, and the weight per metre. For lifting, delivery and pricing by the kilo.
Metal weight calculator
Mild steel, stainless, aluminium, brass and copper. Sheet and plate, flat, round and square bar, box section, round tube and angle.
How the weight is worked out
Weight is the volume of metal times its density. For a 6m length of 40×40×3 box section:
- Cross-section: 2 × 3 × (40 + 40) − 4 × 3² = 444mm².
- Volume: 444mm² × 6000mm = 2,664,000mm³, which is 0.002664m³.
- Weight: 0.002664m³ × 7,850kg/m³ = about 20.9kg, or 3.49kg per metre.
Rolled box section and angle have rounded corners, so a supplier’s table will show a little less than the square-corner sum. Use this for estimating, and the stockholder’s figure when it matters.
Densities used
| Metal | Density (kg/m³) | 1mm sheet, per m² |
|---|---|---|
| Mild steel | 7,850 | 7.85kg |
| Stainless 304 | 7,930 | 7.93kg |
| Stainless 316 | 7,980 | 7.98kg |
| Aluminium | 2,700 | 2.70kg |
| Brass | 8,500 | 8.50kg |
| Copper | 8,960 | 8.96kg |
A handy rule for steel sheet: every millimetre of thickness weighs about 7.85kg per square metre. A 2500×1250 sheet of 3mm mild steel is 3.125m² × 3 × 7.85 = about 74kg.
Aluminium alloys vary a little either side of 2,700kg/m³, and so do the stainless grades.
Ordering the steel as well?
How many sheets
The sheet nesting calculator lays your parts out on the sheet sizes you buy and gives the real count.
How many lengths
The cut length calculator finds the fewest 6m or 7.5m bars of box section, tube or angle for your cut list.
Price the job (Pro)
CutNest turns the layout into a customer quote: material with your markup, cutting time from the actual layout, and VAT.
Straight answers
Try it on your own job
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