Rebar Weight Calculator (Steel Bar Weight per Metre)
Enter the bar diameter, the length of each bar and how many bars you need. See the nominal mass per metre and the total weight of steel, as the Indian standard IS 1786 works it out.
- Total weight
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- Total weight
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- Total weight
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- Nominal mass per metre
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- Cross-sectional area
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- Total length of bar
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Assumptions
- Nominal mass: a round bar of the nominal diameter with steel at 0.00785 kg per mm² per metre (7,850 kg/m³), as IS 1786 clause 7.2.1 sets.
- Real bars may differ from nominal mass within the tolerances in IS 1786 Table 2 (for example ±5% per batch for 12 mm).
- Laps, hooks, bends and cutting waste are not added; include them in the bar length.
Checked 28 October 2026 IS 1786:2008 High strength deformed steel bars and wires for concrete reinforcement: clause 7.2.1 (density 0.00785 kg/mm²/m), Table 1 (nominal mass) and Table 2 (tolerances), with Amendment 1 All sources
How it is calculated
- Area = π × d² ÷ 4 (d in mm, area in mm²)
- Mass per metre = area × 0.00785 kg (IS 1786 clause 7.2.1), which is close to d² ÷ 162
- Total length = length of each bar × number of bars
- Total weight = mass per metre × total length
Worked example
Ten 12 mm bars, each 12 m long.
| You enter | |
|---|---|
| Bar diameter | 12 mm |
| Length of each bar | 12 |
| Length unit | Metres (m) |
| Number of bars | 10 |
| You get | |
| Total weight | 106.54 kg |
| Total weight | 234.88 lb |
| Total weight | 0.1065 t |
| Nominal mass per metre | 0.8878 kg/m |
| Cross-sectional area | 113.1 mm² |
| Total length of bar | 120 m |
10 bars of 12 mm, 120 m of bar in all, weigh about 106.54 kg at 0.8878 kg per metre.
Questions
Where does d² ÷ 162 come from?
Steel weighs about 7,850 kg per cubic metre. A bar of diameter d mm has an area of π × d² ÷ 4 mm², and 1 metre of it weighs that area × 0.00785 kg, which works out to about d² ÷ 162 kg per metre.
Do you show US bar sizes (#3 to #11)?
Not yet. We only add sizes whose published weights we have read in the standard itself. You can type the diameter in millimetres meanwhile (for example a #4 bar is 12.7 mm).
Sources and checks
- IS 1786:2008 High strength deformed steel bars and wires for concrete reinforcement: clause 7.2.1 (density 0.00785 kg/mm²/m), Table 1 (nominal mass) and Table 2 (tolerances), with Amendment 1
- NIST SP 811 (2008), Appendix B: foot and pound conversion factors
Last checked: 28 October 2026. This tool passes 9 automatic tests before every release. How we check our tools
Your numbers never leave your device: the calculation runs in your browser and nothing you type is sent or stored.
Nominal weights for estimating and ordering. Weigh-bridge or mill certificate figures are the ones that count when you buy or check steel. Results are estimates for planning and learning. They are not a design check and do not replace a qualified engineer or your local building/electrical code.