Tools › Steel bar weight and cutting length
Steel bar weight and cutting length
Unit weight from d²/162, cutting length from segments, hooks and bend allowances, total weight and 12 m stock cutting.
Educational use only; not professional design advice; always follow the current code and a licensed engineer.
Educational tool. Bend deductions and hook allowances differ between projects and bending standards (for example IS 2502 and the project specification); the defaults below are common site conventions, so change them to match your drawings.
1. Bar and number
2. Shape
Straight segment lengths along the bar centre line or outer dimensions as your drawing gives them, in mm, separated by spaces.
How it works
A steel bar of diameter d mm has a cross-section of π d²/4 mm². Multiplying by the density of steel, 7850 kg/m³, gives a mass of about 0.00617 d² kg per metre, which is the same as d² divided by 162. Cutting length is the sum of the straight segments, plus the extra length for each hook, minus a small allowance at each bend because the bar stretches on the outside of the bend. Total weight is cutting length times number times unit weight. The stock check shows how many bars can be cut from one stock length and the offcut left.
Worked check: a 12 mm bar has unit weight 144/162 = 0.889 kg/m. With segments 300 + 4000 + 300 mm and two 90° bends at 2d, the cutting length is 4600 − 48 = 4552 mm, weighing 4.05 kg per bar and 80.9 kg for 20 bars.
See the topic page Bar bending schedule.