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TMT Bar Weight Calculator — All Sizes, Per Metre & Per FootInstantly calculate TMT rebar weight using the d²/162 formula for 6mm to 40mm bars

Steel Weight Calculator

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TMT Bar Weight Reference Table — 6mm to 40mm

All values calculated using the standard d²/162.2 formula for mild steel (density 7,850 kg/m³).

Diameter (mm)Weight per Metre (kg/m)Weight per Foot (kg/ft)Weight per 12m Bar (kg)
6mm0.2220.0682.663
8mm0.3950.1204.735
10mm0.6170.1887.398
12mm0.8880.27110.654
16mm1.5780.48118.940
20mm2.4660.75229.593
25mm3.8531.17546.240
28mm4.8331.47358.002
32mm6.3131.92475.758
36mm7.9902.43595.881
40mm9.8643.007118.373

How the d²/162 Formula Works

The d²/162.2 formula is the industry-standard shortcut to calculate the weight of a round steel bar (including TMT rebar) per metre. Here, d is the bar diameter in millimetres.

It is derived from first principles:

  1. Cross-sectional area of a circle = π/4 × d²
  2. Convert mm² to m²: divide by 1,000,000
  3. Multiply by density of steel: 7,850 kg/m³
  4. Simplify: (π/4 × 7850) / 1,000,000 = 1/162.2

Worked Example — 16mm TMT Bar

Step 1: d = 16mm

Step 2: d² = 16 × 16 = 256

Step 3: Weight per metre = 256 / 162.2 = 1.579 kg/m

Step 4: Weight per foot = 1.579 × 0.3048 = 0.481 kg/ft

Step 5: Weight per 12m bar = 1.579 × 12 = 18.943 kg

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TMT Bar Weight Per Metre — Chart for All Sizes →Steel Weight Calculator — Complete Guide With Formulas →← All Calculators