Rebar Weight Calculator
Convert bar diameter and total running length into kilograms and tonnes of reinforcement, with an indicative cost at whatever price per tonne you enter.
Calculator
How the calculation works
Weight per metre in kilograms = the diameter in millimetres squared divided by 162.2, so a 12 mm bar weighs 0.888 kg per metre. Total weight = weight per metre x total running length. The standard bar length in the Saudi market is 12 m, which makes one 12 mm bar about 10.66 kg.
Frequently asked questions
How much does a 12 mm rebar weigh?
0.888 kg per metre, so a standard 12 m bar weighs about 10.66 kg. A 16 mm bar weighs 1.579 kg per metre, or roughly 18.9 kg for a full length.
Where does the number 162.2 come from?
From the density of steel, 7850 kg per cubic metre, applied to a circular cross-section: pi/4 x d² x 10⁻⁶ x 7850 simplifies to d² divided by 162.2.
Does the weight include laps and wastage?
No. Add lap lengths into the running length before entering it, then allow a further 3-7% for cutting waste depending on how tightly the schedule is optimised.
Is steel bought by weight or by length in Saudi Arabia?
By weight, in tonnes, but delivered as 12 m bars. That is exactly why the running length in your schedule and the tonnage on the invoice never match by themselves.
Need a whole bill of quantities priced, not one material?
Upload your BOQ and get every line priced at Saudi market rates in minutes — VAT and all.
Start freeMore free calculators
This calculator is also available in Arabic: حاسبة وزن حديد التسليح.