A 36mm TMT bar weighs 7.990 kg per metre, calculated with the d²/162.2 formula: (36 × 36) ÷ 162.2 = 7.990 kg/m.
A standard 12 m length of 36mm TMT weighs 95.88 kg (7.990 kg/m × 12 m).
Approximately 10 standard 12 m bars of 36mm TMT make one tonne (1,000 ÷ 95.88 kg per bar). Actual counts vary with rolling tolerance under IS 1786.