Brass C36000 Round Bar Weight
Mass per metre and per foot for brass c36000 round bar at 8,500 kg/m³ (ASTM B16 (UNS C36000, free-cutting)). Every figure is for the section as drawn. A 6 m length of this size weighs 25.0 kg (56.1 lb per 20 ft).
At the reference dimensions (d = 25 mm) this section has a cross-sectional area of 490.9 mm², giving 4.172 kg/m (2.804 lb/ft). Against carbon steel's 7,850 kg/m³ that is +8.3 % — the same section in steel would be 3.853 kg/m.
Round Bar — formula and derivation
Area of a round bar
A = π/4 · d²
A = π/4 × d², where d is the outside diameter
Worked through with the default dimensions:
A = π/4 × d²A = 0.785398 × 25²A = 0.785398 × 625.0A = 490.9 mm²
- d
- Diameter — Outside diameter measured across the bar.
Weight follows from the area with no further geometry: m = A × 10⁻⁶ × ρ, where A is in mm², ρ in kg/m³ and m in kg/m. At 8,500 kg/m³ that is 4.1724 kg/m for the reference size above.
Brass round bar — size series
| Diameter | Cross-section | Mass / length |
|---|---|---|
| 6.0 mm | 28.27 mm² · 0.0438 in² | 0.240 kg/m · 0.161 lb/ft |
| 8.0 mm | 50.27 mm² · 0.0779 in² | 0.427 kg/m · 0.287 lb/ft |
| 10 mm | 78.54 mm² · 0.1217 in² | 0.668 kg/m · 0.449 lb/ft |
| 12 mm | 113.10 mm² · 0.1753 in² | 0.961 kg/m · 0.646 lb/ft |
| 14 mm | 153.94 mm² · 0.2386 in² | 1.308 kg/m · 0.879 lb/ft |
| 16 mm | 201.06 mm² · 0.3116 in² | 1.709 kg/m · 1.148 lb/ft |
| 20 mm | 314.16 mm² · 0.4869 in² | 2.670 kg/m · 1.794 lb/ft |
| 25 mm | 490.87 mm² · 0.7609 in² | 4.172 kg/m · 2.804 lb/ft |
| 30 mm | 706.86 mm² · 1.0956 in² | 6.008 kg/m · 4.037 lb/ft |
| 32 mm | 804.25 mm² · 1.2466 in² | 6.836 kg/m · 4.594 lb/ft |
| 40 mm | 1,256.64 mm² · 1.9478 in² | 10.681 kg/m · 7.178 lb/ft |
| 50 mm | 1,963.50 mm² · 3.0434 in² | 16.690 kg/m · 11.215 lb/ft |
| 60 mm | 2,827.43 mm² · 4.3825 in² | 24.033 kg/m · 16.150 lb/ft |
| 80 mm | 5,026.55 mm² · 7.7912 in² | 42.726 kg/m · 28.710 lb/ft |
| 100 mm | 7,853.98 mm² · 12.1737 in² | 66.759 kg/m · 44.860 lb/ft |
Computed for Brass at 8500 kg/m³ (0.3071 lb/in³). ASTM B16 (UNS C36000, free-cutting).
Each row is one nominal size. Because the area is computed from your dimensions rather than read from a mill table, a non-standard size is just as accurate — put it into the calculator above rather than interpolating between rows.
Imperial sizes
Round Bar is also bought in inch sizes. The conversions below are exact (1 in = 25.4 mm by definition), so the metric equivalents are the true millimetre dimensions rather than a rounded nominal figure.
| Stock size | Metric equivalent mm | Cross-section | Mass / length |
|---|---|---|---|
| 1/8 in | 3.17 | 7.92 mm² · 0.0123 in² | 0.067 kg/m · 0.045 lb/ft |
| 3/16 in | 4.76 | 17.81 mm² · 0.0276 in² | 0.151 kg/m · 0.102 lb/ft |
| 1/4 in | 6.35 | 31.67 mm² · 0.0491 in² | 0.269 kg/m · 0.181 lb/ft |
| 5/16 in | 7.94 | 49.48 mm² · 0.0767 in² | 0.421 kg/m · 0.283 lb/ft |
| 3/8 in | 9.52 | 71.26 mm² · 0.1104 in² | 0.606 kg/m · 0.407 lb/ft |
| 1/2 in | 12.70 | 126.68 mm² · 0.1963 in² | 1.077 kg/m · 0.724 lb/ft |
| 5/8 in | 15.88 | 197.93 mm² · 0.3068 in² | 1.682 kg/m · 1.131 lb/ft |
| 3/4 in | 19.05 | 285.02 mm² · 0.4418 in² | 2.423 kg/m · 1.628 lb/ft |
| 7/8 in | 22.22 | 387.95 mm² · 0.6013 in² | 3.298 kg/m · 2.216 lb/ft |
| 1 in | 25.40 | 506.71 mm² · 0.7854 in² | 4.307 kg/m · 2.894 lb/ft |
| 1-1/4 in | 31.75 | 791.73 mm² · 1.2272 in² | 6.730 kg/m · 4.522 lb/ft |
| 1-1/2 in | 38.10 | 1,140.09 mm² · 1.7671 in² | 9.691 kg/m · 6.512 lb/ft |
| 2 in | 50.80 | 2,026.83 mm² · 3.1416 in² | 17.228 kg/m · 11.577 lb/ft |
| 2-1/2 in | 63.50 | 3,166.92 mm² · 4.9087 in² | 26.919 kg/m · 18.089 lb/ft |
| 3 in | 76.20 | 4,560.37 mm² · 7.0686 in² | 38.763 kg/m · 26.048 lb/ft |
| 4 in | 101.60 | 8,107.32 mm² · 12.5664 in² | 68.912 kg/m · 46.307 lb/ft |
Stock sizes in inches, converted exactly at 25.4 mm per inch. Material: Brass C36000 at 8500 kg/m³.
The same round bar in every material
Geometry is fixed and only density changes, so this table is the whole material-selection question in one view. Brass C36000 is highlighted. The percentage column is against carbon steel, which is the figure most quotations are built on.
| Material | Density kg/m³ | lb/in³ | Mass / length kg/m | lb/ft | vs carbon steel |
|---|---|---|---|---|---|
| Carbon Steel | 7,850 | 0.2836 | 3.853 | 2.589 | +0.0 % |
| Stainless Steel 304 | 8,000 | 0.2890 | 3.927 | 2.639 | +1.9 % |
| Stainless Steel 316 | 8,000 | 0.2890 | 3.927 | 2.639 | +1.9 % |
| Stainless Steel 316L | 8,000 | 0.2890 | 3.927 | 2.639 | +1.9 % |
| Stainless Steel 430 | 7,700 | 0.2782 | 3.780 | 2.540 | -1.9 % |
| Aluminum 6061-T6 | 2,700 | 0.0975 | 1.325 | 0.891 | -65.6 % |
| Aluminum 5052-H32 | 2,680 | 0.0968 | 1.316 | 0.884 | -65.9 % |
| Aluminum 7075-T6 | 2,810 | 0.1015 | 1.379 | 0.927 | -64.2 % |
| Copper C11000 | 8,940 | 0.3230 | 4.388 | 2.949 | +13.9 % |
| Brass C36000 | 8,500 | 0.3071 | 4.172 | 2.804 | +8.3 % |
| Bronze C93200 | 8,800 | 0.3179 | 4.320 | 2.903 | +12.1 % |
| Titanium Grade 2 | 4,510 | 0.1629 | 2.214 | 1.488 | -42.5 % |
| Gray Cast Iron | 7,200 | 0.2601 | 3.534 | 2.375 | -8.3 % |
| Lead | 11,340 | 0.4097 | 5.567 | 3.741 | +44.5 % |
| Rigid PVC (Type I) | 1,400 | 0.0506 | 0.687 | 0.462 | -82.2 % |
| HDPE (PE 100) | 960 | 0.0347 | 0.471 | 0.317 | -87.8 % |
Same geometry throughout, so the only variable is density. Carbon steel is highlighted as the baseline.
A note on using this table for costing: mass is not price. Aluminium is roughly a third of steel's mass here, but per kilogram it costs several times more, so a straight swap rarely saves money — what it buys is reduced load on a structure or a vehicle.
About brass c36000
Free-cutting brass, roughly 61 % copper and 3 % lead, and by a wide margin the most machinable common metal — it machines at about three times the speed of 1018 steel with excellent finish. Density 8,500 kg/m³ puts it 8.3 % above carbon steel. The lead that makes it machine so well is also why it is restricted in potable-water contact under many national rules, which pushes fittings toward lead-free silicon or bismuth brasses with densities 0.5–1 % lower.
- Density
- 8,500 kg/m³ = 0.3071 lb/in³ · 1.0828× carbon steel · typical spread ±2 %
- Specification
- ASTM B16 (UNS C36000, free-cutting)
- Equivalents
- EN CW603N · JIS C3604 · GB HPb59-1
- Typical uses
- Fittings and valves · Instrument and clock parts · Electrical connectors · Decorative hardware
Lead content (typically 2.5–3.7 %) restricts use in potable water. Typical density range 8,400–8,700 kg/m³ by composition.
About round bar
Round bar is the only shape whose area grows with the square of a single dimension, so small diameter changes move weight much faster than intuition suggests: going from 25 mm to 28 mm — a 12 % diameter increase — raises the weight per metre by 25 %. This is why shaft stock is normally bought to the nearest preferred diameter rather than machined down from the next size up; the material saved is more than the weight table implies.
Specified by diameter only. For ground and polished stock, add the tolerance class and the straightness limit.
Download this data
Brass round bar — CSV
Both buttons below read the tables rendered on this page, so the file matches what you are looking at. The full catalogue — all 16 materials across all 10 sections — is on the downloads page.
Fields are quoted per RFC 4180, with a UTF-8 byte-order mark so Excel reads the mm² and · characters correctly. Blank lines separate the weight matrix from the area matrix.
Frequently asked questions
How much does brass c36000 round bar weigh?
At the reference dimensions (d = 25 mm) a brass c36000 round bar of this size weighs 4.172 kg/m, or 2.804 lb/ft. The table above lists the figure for every standard size so you can read your size directly instead of scaling.
How is the weight of round bar calculated?
Weight is cross-sectional area × length × density. For this shape the area is A = π/4 · d². At the reference dimensions that gives 490.9 mm², and multiplying by brass c36000's density of 8,500 kg/m³ gives 4.172 kg/m. Nothing is looked up in a table — which is why a non-standard size is calculated just as accurately as a standard one.
Why does brass c36000 weigh more or less than steel?
It is heavier than carbon steel for the same section — about 8 % heavier at 8,500 kg/m³. Density is the only variable: the cross-sectional area depends purely on geometry, so a round bar of the same dimensions has the same area in every material and the mass simply scales with density. In this case the ratio is 1.0828× carbon steel.
What is the cross-sectional area of a round bar?
The area depends only on the dimensions, not on the material, so it is identical whichever material you select: at the reference dimensions it is 490.9 mm² (0.7609 in²). That is the number you would enter into a stress or deflection calculation, and it is why changing material on this page never changes the area column.
Does a brass round bar weigh the same as a brass part of a different shape?
No, and the difference is larger than most people expect. At equal nominal size, a square bar is 27.3 % heavier than a round bar, and a hollow section is typically 60–80 % lighter than the solid bar it replaces. Weight follows area, and area changes faster than dimensions do — which is exactly why this needs calculating rather than estimating.
Should I use Brass weight or carbon steel weight for costing?
Use the material you are actually buying. At 8,500 kg/m³ against carbon steel's 7,850 kg/m³, the same round bar differs by 8.3 % in mass. On a per-metre quote that is invisible; on a fabricated tonnage it is the difference between a margin and a loss. This page computes the steel figure as 3.853 kg/m for comparison.
Other materials, same round bar
The same geometry in every material, so the only variable is density.
- Carbon steel round bar — 7850 kg/m³
- SS 304 round bar — 8000 kg/m³
- SS 316 round bar — 8000 kg/m³
- AL 6061 round bar — 2700 kg/m³
- Copper round bar — 8940 kg/m³
- HDPE round bar — 960 kg/m³
- PVC round bar — 1400 kg/m³
- AL 5052 round bar — 2680 kg/m³
Other Brass sections
The same density applied to every shape the site covers.
- Brass square bar — A = a²
- Brass hexagonal bar — A = (√3/2) · AF² ≈ 0.8660 · AF²
- Brass flat bar — A = w · t
- Brass plate — A = w · t
- Brass round tube — A = π/4 · (D² − d²), d = D − 2t
- Brass square tube — A = a² − (a − 2t)²
Reference data and tools
- Metal weight overview — how the calculation works
- All 16 materials — densities and specifications
- All 10 sections — formulas and size series
- Density chart — lightest to heaviest
- Metal weight calculator — any size, any material
- All calculators — metal weight and pipe weight
- Download the data — CSV, generated from the same source
- Cross-reference tables — DN / NPS / material equivalents
- Methodology and sources — where every number comes from
Round Bar area from A = π/4 · d². Mass computed as area × length × density at 8,500 kg/m³ (ASTM B16 (UNS C36000, free-cutting)). No weight on this page is copied from a published table — which is why figures can differ in the last significant digit from a mill's chart calculated at a nominal density.
- Elementary plane geometry. The circle, polygon and hollow-section area formulas.
- ASTM material specifications for each grade named in the material entry (A36, A240/A276, B209/B211/B221, B152/B16/B505, B265/B348, A48, B29, D1784, D3350).
- BIPM / NIST definitional constants: international inch = 25.4 mm, foot = 0.3048 m, pound = 0.45359237 kg.
Dataset version 2026.09.1 · dimensions last verified against source 2026-09-21. Found an error? Report it — corrections are issued with a version bump.