How to calculate TMT bar weight
TMT (Thermo-Mechanically Treated) bars are reinforcement steel, so their weight per metre uses the well-known D²/162 rule, where D is the bar diameter in millimetres:
Weight (kg/m) = D² ÷ 162
This comes from the circular cross-sectional area (π/4 × D²) multiplied by the density of steel (7,850 kg/m³). Multiply the weight per metre by the bar length and the number of bars to get the total. Pick "Reinforcement Bar (Rebar)" in the calculator above (already selected) and enter the diameter.
TMT bar weight chart (kg per metre)
| Bar diameter | Weight (kg/m) | Per 12 m bar |
|---|---|---|
| 8 mm | 0.395 | 4.74 kg |
| 10 mm | 0.617 | 7.40 kg |
| 12 mm | 0.888 | 10.66 kg |
| 16 mm | 1.578 | 18.94 kg |
| 20 mm | 2.466 | 29.59 kg |
| 25 mm | 3.854 | 46.25 kg |
| 32 mm | 6.313 | 75.76 kg |