Steel weight calculator — rebar and plate

Bar bending schedules and steel take-offs both come down to one figure: mass per metre. For round bar that is d²/162 kg/m; for plate it is thickness × area × 7850 kg/m³. Both are below, so a detailer can check a schedule total without opening the model.

steel weight calculator

Total rebar weight
948.1kg
Rebar mass per metre
1.58 kg/m (2,090 lb total)
Plate weight
157 kg (0.157 t)
Combined tonnage
1.105t

Formula

rebar kg/m = d² ÷ 162 · plate kg = thickness (m) × area (m²) × 7850

d²/162 is the standard simplification of density × cross-sectional area for steel at 7850 kg/m³. It gives 1.58 kg/m for 16 mm bar, which matches published bar schedules.

Worked examples

InputResult
50 no. 16 mm bars × 12 m948.1 kg (1.58 kg/m)
12 mm bar0.888 kg/m
10 mm plate, 2 m²157 kg

Questions

Where does the 162 in d²/162 come from?

It is 4000 ÷ (π × 7.85), the algebraic simplification of area × density for a round steel bar with the diameter in millimetres. It returns kilograms per metre directly.

Should I add laps and wastage to a rebar take-off?

Yes. Add lap lengths per the design code and typically 3–5% cutting wastage. A Tekla or Revit bar schedule reports cut lengths only, not site wastage.

Does this work for structural sections?

No — use the published mass per metre from the section tables for UB, UC, HEA, IPE and hollow sections. This calculator covers round bar and flat plate.

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