Steel weight calculator
To calculate steel weight, choose a material and profile and enter the dimensions in millimetres: you get the weight per piece, per metre and in total.
Example: Material: Steel · Profile: Round bar · Length 1,000 mm · Diameter 20 mm · Quantity 1 → Result: Steel: 2.466 kg in total (2.466 kg each, 1 pcs). Source: Wikipedia – Dichte: Dichten ausgewählter Metalle (Stahl 7,85 g/cm³, Aluminium 2,70 g/cm³, Kupfer 8,96 g/cm³). Updated: .
How it is calculated
Weight is volume times density. A steel round bar of 20 mm diameter weighs 2.47 kg per metre; a steel plate of 1 m × 1 m × 1 mm weighs exactly 7.85 kg.
How it is calculated
The dimensions give the cross-section area in mm²: round π/4·d², square a², hexagon √3/2·AF², flat bar width·thickness, round pipe π·t·(D − t), square tube a² − (a − 2t)². Times length gives the volume, times density the weight: kg per metre = area in mm² · density / 1000. Stainless steel is taken at 7.9 g/cm³, aluminium at 2.70 g/cm³.
Good to know
- For the same volume aluminium weighs only about a third of steel, copper about 14 % more.
- Hollow sections with corner radii are slightly lighter than the value with sharp corners.
- For freight and structural design, rely on the manufacturer's data (datasheet, standard tables).
Frequently asked questions
How do you calculate the weight of steel?
Volume in cm³ times density 7.85 g/cm³, divided by 1000. For a 1000 × 500 × 5 mm plate that is 2500 cm³ · 7.85 / 1000 = 19.6 kg.
How much does a metre of 20 mm round bar weigh?
About 2.47 kg. In general: kg/m ≈ d² · 0.00617 with d in mm.
What is the density of stainless steel?
Austenitic stainless steel such as 304 is around 7.9 g/cm³, a little above ordinary structural steel.
How heavy is an aluminium sheet?
2.7 kg per square metre per millimetre of thickness. A 1 × 2 m sheet that is 2 mm thick weighs 10.8 kg.
Sources and legal basis
- Wikipedia – Dichte: Dichten ausgewählter Metalle (Stahl 7,85 g/cm³, Aluminium 2,70 g/cm³, Kupfer 8,96 g/cm³)
- Wikipedia – Stahl: Dichte von Stahl 7,85 g/cm³
- Wikipedia – Nichtrostender Stahl: Dichte von rund 7,9 g/cm³ (austenitische Güten)
As of: · Editorial policy
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