Updated November 2, 2026 · Indumor
“So how much does that weigh?” It is the first thing asked by whoever has to load the pickup, and it usually gets a ballpark answer. With this chart there is no need: here are the kilograms per meter of round, square and hexagonal steel bars, in millimeters and in inches.
| Size mm | Round kg/m | Square kg/m | Hexagonal kg/m |
|---|---|---|---|
| 6 | 0.222 | 0.283 | 0.245 |
| 8 | 0.395 | 0.502 | 0.435 |
| 10 | 0.617 | 0.785 | 0.680 |
| 12 | 0.888 | 1.13 | 0.979 |
| 14 | 1.21 | 1.54 | 1.33 |
| 16 | 1.58 | 2.01 | 1.74 |
| 18 | 2.00 | 2.54 | 2.20 |
| 20 | 2.47 | 3.14 | 2.72 |
| 22 | 2.98 | 3.80 | 3.29 |
| 25 | 3.85 | 4.91 | 4.25 |
| 28 | 4.83 | 6.15 | 5.33 |
| 30 | 5.55 | 7.07 | 6.12 |
| 32 | 6.31 | 8.04 | 6.96 |
| 35 | 7.55 | 9.62 | 8.33 |
| 38 | 8.90 | 11.3 | 9.82 |
| 40 | 9.86 | 12.6 | 10.9 |
| 45 | 12.5 | 15.9 | 13.8 |
| 50 | 15.4 | 19.6 | 17.0 |
| 55 | 18.7 | 23.7 | 20.6 |
| 60 | 22.2 | 28.3 | 24.5 |
| 65 | 26.0 | 33.2 | 28.7 |
| 70 | 30.2 | 38.5 | 33.3 |
| 75 | 34.7 | 44.2 | 38.2 |
| 80 | 39.5 | 50.2 | 43.5 |
| 90 | 49.9 | 63.6 | 55.1 |
| 100 | 61.7 | 78.5 | 68.0 |
| 110 | 74.6 | 95.0 | 82.3 |
| 120 | 88.8 | 113 | 97.9 |
| 130 | 104 | 133 | 115 |
| 140 | 121 | 154 | 133 |
| 150 | 139 | 177 | 153 |
| Size in | mm | Round kg/m | Square kg/m | Hexagonal kg/m |
|---|---|---|---|---|
| 1/4 | 6.35 | 0.249 | 0.317 | 0.274 |
| 5/16 | 7.94 | 0.388 | 0.495 | 0.428 |
| 3/8 | 9.53 | 0.559 | 0.712 | 0.617 |
| 7/16 | 11.11 | 0.761 | 0.969 | 0.840 |
| 1/2 | 12.70 | 0.994 | 1.27 | 1.10 |
| 9/16 | 14.29 | 1.26 | 1.60 | 1.39 |
| 5/8 | 15.88 | 1.55 | 1.98 | 1.71 |
| 3/4 | 19.05 | 2.24 | 2.85 | 2.47 |
| 7/8 | 22.23 | 3.05 | 3.88 | 3.36 |
| 1 | 25.40 | 3.98 | 5.06 | 4.39 |
| 1 1/8 | 28.58 | 5.03 | 6.41 | 5.55 |
| 1 1/4 | 31.75 | 6.22 | 7.91 | 6.85 |
| 1 3/8 | 34.93 | 7.52 | 9.58 | 8.29 |
| 1 1/2 | 38.10 | 8.95 | 11.4 | 9.87 |
| 1 3/4 | 44.45 | 12.2 | 15.5 | 13.4 |
| 2 | 50.80 | 15.9 | 20.3 | 17.5 |
| 2 1/4 | 57.15 | 20.1 | 25.6 | 22.2 |
| 2 1/2 | 63.50 | 24.9 | 31.7 | 27.4 |
| 3 | 76.20 | 35.8 | 45.6 | 39.5 |
| 3 1/2 | 88.90 | 48.7 | 62.0 | 53.7 |
| 4 | 101.60 | 63.6 | 81.0 | 70.2 |
How do you work out the weight of a round bar?
Square the diameter in millimeters and multiply by 0.006165. A 25 mm bar: 25 × 25 × 0.006165 = 3.85 kg/m. A 6 m bar weighs 23.1 kg. Done.
And a square or hexagonal one?
Square: side squared times 0.00785. Hexagonal: across-flats size squared times 0.0068. Across flats, not across corners: it is the size of the wrench that grips it.
And a flat bar?
Thickness times width times 0.00785. A 6 × 50 mm flat weighs 2.36 kg/m.
Does it work for stainless or aluminum?
Yes, by changing the density. The chart uses 7.85 kg/dm³. Stainless 304 runs about 7.9; 316, about 8.0; aluminum, 2.70; brass, around 8.5 depending on the alloy; and copper, 8.9. Multiply the chart weight by the new density and divide by 7.85. The calculator already has those materials.
And rebar?
Deformed bars with 420 MPa yield come under two standards: ADN 420 (IRAM-IAS U 500-528) and ADN 420 S (U 500-207), and under the CIRSOC 201-2025 code the weldable one is the S. They are sold in 12 m bars, with these nominal weights:
| Diameter mm | Area cm² | Nominal weight kg/m | 12 m bar kg |
|---|---|---|---|
| 6 | 0.283 | 0.222 | 2.66 |
| 8 | 0.503 | 0.395 | 4.74 |
| 10 | 0.785 | 0.617 | 7.40 |
| 12 | 1.13 | 0.888 | 10.7 |
| 16 | 2.01 | 1.58 | 18.9 |
| 20 | 3.14 | 2.47 | 29.6 |
| 25 | 4.91 | 3.85 | 46.2 |
| 32 | 8.04 | 6.31 | 75.7 |
| 40 | 12.57 | 9.86 | 118.3 |
Does the chart give the exact weight of the bar that arrives?
It gives the nominal weight. A real bar has rolling tolerance and can run a few points over or under. For rebar, one Argentine manufacturer states ±5 % on mass below 10 mm and ±3 % from 10 mm up. For buying and loading, that is plenty. For a certified scale, it is not.
Have a list of bars to cut or machine?
We cut and machine them to size in our shop.
© Indumor 2010–2026 — Industrial steel fabrication, Córdoba, Argentina
