TMT Bar Weight Chart 2026 — Every Size, Weight Per Metre, Per Piece & Per Bundle
Introduction: Why Getting Steel Weight Right Can Save Lakhs
Every RCC construction project begins with one critical calculation: how much steel do I need? Underestimate, and you'll face mid-construction procurement delays and price-spike exposure. Overestimate, and you've locked up capital in idle inventory. The foundation of every accurate steel estimate is the TMT bar weight chart.
This guide gives you the most comprehensive, IS 1786-aligned TMT bar weight reference available, covering every standard diameter from 6mm to 40mm, with weights per metre, per standard 40-foot rod, per bundle, and per metric tonne. Before your next project briefing, make sure to go through this guide.
TMT Bar Weight Chart — All Standard Sizes (IS 1786:2008)
The theoretical weight per metre for any circular steel bar is calculated using the standard formula:
| 📐 Weight Formula (IS 1786) Weight per metre (kg/m) = D² ÷ 162.28 | Where D = Nominal diameter in millimetres |
|---|
| Dia. (mm) | Wt./metre (kg) | Wt./40ft Rod (kg) | Rods per 100 kg | Wt./Bundle (kg) | Rods/Bundle | Typical Use |
|---|---|---|---|---|---|---|
| 6 mm | 0.222 | 2.707 | 36.9 | ~54 | ~20 | Distribution steel, light stirrups |
| 8 mm | 0.395 | 4.819 | 20.7 | ~48 | 10 | Slabs, lintels, stirrups, ties |
| 10 mm | 0.617 | 7.527 | 13.3 | ~75 | ~10 | Slabs (main reinforcement), secondary beams, stirrups |
| 12 mm | 0.888 | 10.834 | 9.2 | ~108 | ~10 | Slabs (main reinforcement), beams, small columns |
| 16 mm | 1.578 | 19.276 | 5.2 | ~96 | ~5 | Columns, beams, retaining walls |
| 20 mm | 2.470 | 30.134 | 3.3 | ~120 | ~4 | Heavy columns, foundations |
| 25 mm | 3.853 | 46.97 | 2.1 | ~141 | ~3 | Pile caps, bridge beams |
| 28 mm | 4.834 | 59.38 | 1.7 | ~118 | ~2 | Heavy infrastructure works |
| 32 mm | 6.313 | 76.982 | 1.3 | ~154 | ~2 | Flyovers, dams, marine structures |
| 36 mm | 7.990 | 98.08 | 1.0 | ~196 | ~2 | Large piles, heavy engineering structures |
[Table 1] IS 1786:2008 standard TMT bar weights. Bundle quantities are indicative — actual bundles vary by manufacturer. 1 rod = 12.2 metres (40 feet). Weights may vary within the IS 1786 permissible tolerance limits.
How to Calculate TMT Bar Quantity for Any RCC Structure
Step 1: Get the Structural Drawing
Obtain the BIS-compliant structural drawing from your licensed structural engineer. This shows bar diameters, spacing, and lengths for every structural member (columns, beams, slabs, footings, stirrups).
Step 2: Calculate Bar Length for Each Member
For a rectangular slab: Main bars = (Slab length ÷ bar spacing + 1) × slab width + 2 × cover lap allowance. Distribution bars = (Slab width ÷ bar spacing + 1) × slab length + 2 × cover lap allowance.
Step 3: Convert Length to Weight
Total length (m) × Weight per metre (from the chart above) = Total weight in kg. Add 5% for lapping, bending, and cutting wastage.
Step 4: Convert Weight to Number of Rods
Total weight in kg ÷ weight per 40ft rod = Number of rods required. Round up to the nearest whole number.
| Quick Example G+0 RCC slab of 1,000 sq ft (93 sq m) using 12mm @ 150mm spacing: Main bars ≈ (93÷0.15+1) × 3.7m + lap = ~665m. Distribution bars ≈ of similar length. Total 12mm bar needed ≈ 1,330m × 0.888 kg/m = 1,181 kg ≈ 108 rods of 40ft. Always verify with your structural engineer. For a free steel estimate, contact Arun Plus TMT. |
|---|
TMT Bar Weight Per Piece — Quick Reference for Procurement
| Diameter | Weight of 1 Rod (40ft) | Approx. Rods in 1 Tonne |
|---|---|---|
| 8 mm | 4.819 kg | 207 rods |
| 10 mm | 7.527 kg | 133 rods |
| 12 mm | 10.834 kg | 92 rods |
| 16 mm | 19.276 kg | 52 rods |
| 20 mm | 30.134 kg | 33 rods |
| 25 mm | 46.97 kg | 21 rods |
| 32 mm | 76.982 kg | 13 rods |
[Table 2] Practical procurement reference — rods per tonne for common diameters
Q: What is the weight of a 12mm TMT bar of 40 feet?
A: A standard 40-foot (12.2 metre) 12mm TMT bar weighs 0.888 kg/m × 12.2 m = approximately 10.83 kg per piece. Actual bundle Weights may vary within IS 1786 permissible tolerance limits.
Q: How many 8mm TMT bars are there in 1 kg?
A: Since a 40-foot 8mm TMT bar weighs approximately 4.82 kg, there are approximately 0.206 rods per kg, or about 1 metre of 8mm bar per kg (since 0.395 kg/m means 1 kg = 2.53 metres). For a full 40-foot rod count per 100 kg, that's approximately 20–21 rods.
Q: What is the formula for TMT bar weight per metre?
A: The standard BIS formula is: Weight (kg/m) = D² ÷ 162.28, where D is the nominal bar diameter in millimetres. Example for 16mm: 16² ÷ 162.28 = 256 ÷ 162.28 = 1.578 kg/m.
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Get a Quote →Frequently Asked Questions
What is the weight of a 12mm TMT bar of 40 feet?
A standard 40-foot (12.2 metre) 12mm TMT bar weighs 0.888 kg/m × 12.2 m = approximately 10.83 kg per piece. Actual bundle weights may vary within IS 1786 permissible tolerance limits.
How many 8mm TMT bars are there in 1 kg?
Since a 40-foot 8mm TMT bar weighs approximately 4.82 kg, there are approximately 0.206 rods per kg. For a full 40-foot rod count per 100 kg, that's approximately 20–21 rods.
What is the formula for TMT bar weight per metre?
The standard BIS formula is: Weight (kg/m) = D² ÷ 162.28, where D is the nominal bar diameter in millimetres. Example for 16mm: 16² ÷ 162.28 = 256 ÷ 162.28 = 1.578 kg/m.