TMT bar weight calculator
Weight of TMT bars (saria) by diameter: kg per metre, per 12 m bar and for any number of bars, from the IS 1786 formula d²/162.2.
Calculate
- Weight per metre
- 0.888 kg
- Weight per bar
- 10.65 kg
- Total weight
- 1,065.35 kg (1.065 tonnes)
How it is calculated
A steel bar's weight per metre is d² ÷ 162.2 kg, where d is the diameter in millimetres. The figure comes from the density of steel, 7,850 kg/m³, and is the basis of the nominal masses in IS 1786.
Multiply by the bar length (12 m as supplied, unless cut) for the weight of one bar, and by the number of bars for the total. A 12 mm bar, for example, weighs 0.888 kg per metre and 10.65 kg per 12 m bar.
Rolling tolerance means a delivered bar can weigh a few per cent more or less than the nominal figure, which is why bars are sold by weight and checked on a weighbridge.
An estimate for ordering material, not a structural design. Your engineer's drawings and site measurements decide the final quantities.
Questions
- What is the formula for TMT bar weight?
- Weight in kg per metre = d² ÷ 162.2, with d the diameter in mm. Multiply by the length in metres for one bar.
- How many 12 mm bars are in one tonne?
- A 12 m length of 12 mm bar weighs about 10.65 kg, so a tonne is about 94 bars.
- How much does an 8 mm and a 16 mm bar weigh?
- 8 mm weighs 0.395 kg per metre (4.73 kg per 12 m bar); 16 mm weighs 1.58 kg per metre (18.94 kg per 12 m bar).
- What length are TMT bars sold in?
- Usually 12 metres. Smaller diameters such as 6 and 8 mm are also sold in coils.