Stainless steel round bar weight calculator
A Ø10 stainless round bar weighs 0.620 kg/m, Ø20 2.482, Ø30 5.584 kg/m (1.4301). A table of 23 diameters from 3 to 100 mm with the mass for 304 and 316L, the formula for square and hexagon bar, and a calculator for any diameter.
Short answer
The weight of stainless round bar is 0.006205 · d² kg/m for 1.4301 (π/4 · d² · 7.90 / 1000, d in mm) and 0.006283·d² for 316L. A Ø12 bar weighs 0.893 kg/m, Ø20 2.482 kg/m, Ø50 15.51 kg/m; a 6 m length of Ø20 is 14.9 kg. The diameter table is below.
Stainless round bar weight: diameters 3–100 mm
Stainless bar (EN 10088-3) is sold cold drawn to h9 or peeled and ground, usually in 3 or 6 m lengths. Masses are from the nominal size:
| Diameter, mm | Cross-section, mm² | kg/m — 1.4301 (304) | kg/m — 1.4404 (316L) | 6 m length, kg |
|---|---|---|---|---|
| 3 | 7 | 0.056 | 0.057 | 0.34 |
| 4 | 13 | 0.099 | 0.101 | 0.60 |
| 5 | 20 | 0.155 | 0.157 | 0.93 |
| 6 | 28 | 0.223 | 0.226 | 1.34 |
| 8 | 50 | 0.397 | 0.402 | 2.38 |
| 10 | 79 | 0.620 | 0.628 | 3.72 |
| 12 | 113 | 0.893 | 0.905 | 5.36 |
| 14 | 154 | 1.216 | 1.232 | 7.30 |
| 15 | 177 | 1.396 | 1.414 | 8.38 |
| 16 | 201 | 1.588 | 1.608 | 9.53 |
| 18 | 254 | 2.010 | 2.036 | 12.06 |
| 20 | 314 | 2.482 | 2.513 | 14.89 |
| 22 | 380 | 3.003 | 3.041 | 18.02 |
| 25 | 491 | 3.878 | 3.927 | 23.27 |
| 30 | 707 | 5.584 | 5.655 | 33.51 |
| 35 | 962 | 7.601 | 7.697 | 45.60 |
| 40 | 1 257 | 9.927 | 10.053 | 59.56 |
| 45 | 1 590 | 12.564 | 12.723 | 75.39 |
| 50 | 1 963 | 15.512 | 15.708 | 93.07 |
| 60 | 2 827 | 22.337 | 22.619 | 134.02 |
| 70 | 3 848 | 30.403 | 30.788 | 182.42 |
| 80 | 5 027 | 39.710 | 40.212 | 238.26 |
| 100 | 7 854 | 62.046 | 62.832 | 372.28 |
Mass goes with the square of the diameter: a Ø40 bar weighs four times a Ø20 (9.93 against 2.48 kg/m). When buying by the kilogram that is a quick check of the invoice.
Where the number comes from
The area of a circle is π·d²/4; for Ø20 that is 314.2 mm², times 7.90 / 1000 = 2.482 kg/m. Hence the shortcut 0.006205 · d² for 304 and 0.006283 · d² for 316L. Grade densities to EN 10088-1:
| EN grade | Designation | AISI / UNS | Structure | Density, g/cm³ | Difference from 1.4301 |
|---|---|---|---|---|---|
| 1.4301 | X5CrNi18-10 | 304 | austenitic | 7.90 | 0 |
| 1.4307 | X2CrNi18-9 | 304L | austenitic | 7.90 | 0 |
| 1.4541 | X6CrNiTi18-10 | 321 | austenitic | 7.90 | 0 |
| 1.4401 | X5CrNiMo17-12-2 | 316 | austenitic | 8.00 | +1.3 % |
| 1.4404 | X2CrNiMo17-12-2 | 316L | austenitic | 8.00 | +1.3 % |
| 1.4571 | X6CrNiMoTi17-12-2 | 316Ti | austenitic | 8.00 | +1.3 % |
| 1.4016 | X6Cr17 | 430 | ferritic | 7.70 | −2.5 % |
| 1.4462 | X2CrNiMoN22-5-3 | 2205 | duplex | 7.80 | −1.3 % |
Shafts and spindles are more often 1.4404 or 1.4571 (8.00), fasteners and fittings 1.4301 (7.90). Duplex 1.4462 for pump and agitator shafts is 7.80 — 1.3 % lighter than 304.
Square and hexagon bar
Square bar: a² · 7.90 / 1000. A 20 square weighs 3.160 kg/m, 27 % more than a Ø20 round. In the calculator choose the “Square bar” profile.
Hexagon bar (size across flats s): area = 0.866 · s², mass 0.006841 · s² kg/m for 304. A 20 A/F hexagon weighs 2.737 kg/m, 30 A/F 6.157 kg/m. The calculator has no hexagon — use the formula.
How much does a bundle weigh
Example: twelve Ø16 bars, 3 m each. A metre weighs 1.588 kg, a bar 4.77 kg, the bundle 57.2 kg. The real weight of h9 drawn bar is a touch lower, because the h9 tolerance is minus only.
The same bar in another material
A Ø20 bar weighs 2.466 kg/m in mild steel, 2.482 in stainless and 0.848 kg/m in aluminium (aluminium round bar). Mild steel in every shape — steel weight calculator; stainless sheet and tube — stainless sheet, stainless tube. Welding 304 and 316L bar and shafts — welding stainless steel.
Frequently asked questions
How much does a 20 mm stainless round bar weigh?
2.482 kg/m in 1.4301 (304) and 2.513 kg/m in 1.4404 (316L). A 3 m bar is 7.45 kg, a 6 m one 14.89 kg.
How much does a 10 mm stainless round bar weigh?
0.620 kg/m (304), so 1.86 kg for a 3 m length. Ø8 weighs 0.397 kg/m, Ø12 0.893 kg/m.
How do I work out the weight of hexagon bar?
The area of a hexagon with size across flats s is 0.866 · s², so mass = 0.006841 · s² kg/m for 304. A 24 A/F bar weighs 3.941 kg/m.
Why does the bar from the stockist weigh less than the table?
Drawn bar is made to an h9 tolerance — minus only — and peeled bar to h10 or h11, also minus only. The difference is usually a fraction of a per cent on thick bar and up to 1–2 % on thin.
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