Steel / TMT Bar Weight Calculator

How it works

How to use the steel weight

Steel reinforcement is bought by weight but specified by diameter and length. The standard site formula for the theoretical weight of a round bar is D² ÷ 162 kg per metre, where D is the diameter in millimetres. It comes from steel's density of about 7,850 kg/m³. A 12 mm bar weighs 0.889 kg per metre, so one 12 m length weighs about 10.67 kg.

Enter the diameter, the length of each bar and how many bars you have, and the calculator gives the weight per metre and per foot, the weight of a standard 12 m bar, how many 12 m bars make a tonne and the total weight in kilograms and tonnes.

Actual weights vary within the tolerance allowed by IS 1786, so a dealer's weighbridge figure can differ slightly from the theoretical one. Use this to check bills, compare quotes per tonne and estimate quantities from a bar bending schedule.

1. Choose the bar diameter.
2. Enter the length of each bar in metres or feet.
3. Enter the number of bars.
4. Read weight per metre, per bar and total.