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Rebar Weight Calculator
IS 1786-based unit weight reference — multiple bar sizes, meter/feet input, instant kg / ton / lb totals
| Dia (mm) | Qty | Length | Unit | Weight per Bar (kg) | Row Total (kg) |
|---|
Total Weight (All Rebars)
Total (kg)
0.000
Total (lb)
0.000
Total (Metric Ton)
0.000000
Total (Quintal)
0.00000
Formula (IS 1786): W = d² / 162 kg/m, where d = bar diameter in mm.
1 kg = 2.20462 lb | 1 metric ton = 1000 kg | 1 quintal = 100 kg
1 kg = 2.20462 lb | 1 metric ton = 1000 kg | 1 quintal = 100 kg
Downloads the results as an Excel (.xls) file to your device.
Rebar Weight Calculator Formula
If you'd rather skip the arithmetic, our Rebar Weight Calculator automates everything below — select a bar size, enter length and quantity, and it returns weight in kg, metric ton, and pounds instantly.The standard rebar weight formula
Reinforcement bars are manufactured to a consistent density, so their weight per unit length can be derived directly from the bar's nominal diameter without needing to weigh anything. Starting from the basic mass equation for a cylinder:
W = (π/4) × d² × ρ × L
where d is the bar diameter in meters, ρ is the density of steel (7850 kg/m³), and L is the bar length in meters. When diameter is expressed in millimeters instead of meters, the constants collapse into the simplified form structural engineers use on site:
W (kg/m) = d² ÷ 162
This is the formula referenced across ISO 6935-covered reinforcement standards and is the basis BNBC 2020 (Part 6, structural design provisions) assumes when specifying reinforcement quantities and detailing schedules. It applies to deformed bars at their nominal diameter — the manufactured rib profile adds a small tolerance that doesn't materially affect the calculated weight for estimating purposes.
