Metal weight, by material and section
16 materials × 10 section shapes = 160 size-series tables. Every number is computed as area × length × density from closed-form geometry and a specification density — nothing is copied from a published chart, and nothing is interpolated.
Start with the pages people actually use
These are the twelve combinations that come up most often in a take-off. Each is shown at the site’s standard reference size so the numbers can be compared down the column.
| Material and shape | Reference sizemm | Cross-sectionmm² | Mass | Imperial |
|---|---|---|---|---|
| Carbon steel · Round Bar | d 25 | 490.9 | 3.853 kg/m | 2.589 lb/ft |
| Carbon steel · Plate | w 1000 × t 10 | 10,000.0 | 78.50 kg/m² | 16.08 lb/ft² |
| Carbon steel · Square Tube | a 40 × t 3 | 444.0 | 3.485 kg/m | 2.342 lb/ft |
| Carbon steel · Round Tube | D 50 × t 3 | 443.0 | 3.477 kg/m | 2.337 lb/ft |
| Carbon steel · Angle (L Section) | a 50 × b 50 × t 5 | 475.0 | 3.729 kg/m | 2.506 lb/ft |
| Carbon steel · Channel (U Section) | h 200 × b 75 × t_w 8 × t_f 10 | 2,940.0 | 23.079 kg/m | 15.508 lb/ft |
| SS 304 · Round Bar | d 25 | 490.9 | 3.927 kg/m | 2.639 lb/ft |
| SS 304 · Plate | w 1000 × t 10 | 10,000.0 | 80.00 kg/m² | 16.39 lb/ft² |
| AL 6061 · Square Tube | a 40 × t 3 | 444.0 | 1.199 kg/m | 0.806 lb/ft |
| AL 6061 · Plate | w 1000 × t 10 | 10,000.0 | 27.00 kg/m² | 5.53 lb/ft² |
| Copper · Round Bar | d 25 | 490.9 | 4.388 kg/m | 2.949 lb/ft |
| HDPE · Round Tube | D 50 × t 3 | 443.0 | 0.425 kg/m | 0.286 lb/ft |
Plate rows are per square metre; every other row is per metre of length. This is not an inconsistency — plate is bought by area, and quoting it per metre of a notional strip would be less useful, not more consistent.
Two ways into the data
By material
16 materials from HDPE at 960 kg/m³ to lead at 11,340 kg/m³, each with the specification its density represents and links to all 10 shapes.
By section shape
10 shapes with the exact area formula for each, the size series it is stocked in, and links to all 16 materials.
Density chart
Every material lightest to heaviest with its relative mass against carbon steel — the single most-useful page when the question is “what else could this be made from?”.
Metal weight calculator
Any dimensions, any material, a multi-line bill of materials, and a reverse lookup that answers the question a table cannot: given a mass limit, how much length do I get?
How the calculation works
There is one identity behind every page in this cluster:
m = A × 10⁻⁶ × ρ
where A is the cross-sectional area in mm², ρ the density in kg/m³, and m the mass in kg/m. The factor 10⁻⁶ is just mm² → m². Three consequences follow, and they are worth stating because each is a way people get this wrong:
- Area depends only on geometry. Changing material never changes the area column — that is why the area matrix on each tube page is identical for all 16 materials, and why it is genuinely reusable.
- Mass is exactly linear in density. A 1 % density error is a 1 % weight error, nothing more and nothing less. Substituting 316 for carbon steel is +1.9 %.
- Mass is quadratic in a round bar’s diameter, but linear in a plate’s thickness. Area grows with the square of diameter and only linearly with thickness, which is why a small diameter change moves weight much faster than a small thickness change does.
We do not tabulate section properties. Second moment of area, section modulus and radius of gyration belong to the mill’s own table for a named shape (UPN, IPE, HEA, AISC W/C/MC), and reproducing them badly would be worse than not having them. The size series here are round-numbered geometry for estimating, and the weight is exact for the dimensions shown — see methodology for the full statement.
Densities at a glance
The eight materials that cover most specifying decisions. All 16 are on the density chart of all materials.
| Material | Density kg/m³ | lb/in³ | vs carbon steel | Specification density represents |
|---|---|---|---|---|
| Carbon Steel | 7,850 | 0.2836 | +0.0 % | ASTM A36 / AISI 1018 / EN 10025 S275 |
| Stainless Steel 304 | 8,000 | 0.2890 | +1.9 % | ASTM A240 / A276 (UNS S30400) |
| Aluminum 6061-T6 | 2,700 | 0.0975 | -65.6 % | ASTM B221 / B209 (T6 temper) |
| Copper C11000 | 8,940 | 0.3230 | +13.9 % | ASTM B152 / B187 (UNS C11000, ETP) |
| Titanium Grade 2 | 4,510 | 0.1629 | -42.5 % | ASTM B265 / B348 (UNS R50400) |
| Gray Cast Iron | 7,200 | 0.2601 | -8.3 % | ASTM A48 Class 30 / ISO 185 |
| Lead | 11,340 | 0.4097 | +44.5 % | ASTM B29 (UNS L50049, chemical lead) |
| HDPE (PE 100) | 960 | 0.0347 | -87.8 % | ISO 4427 / ASTM D3350 (PE 100 black) |
Relative figures are against carbon steel at 7,850 kg/m³. A negative percentage means lighter.
Download the whole cluster
Metal weight data
Three CSVs covering every table on this site, generated at build time from the same source the pages render.
Licence, provenance and column definitions are on the downloads page.
Frequently asked questions
How do I calculate the weight of a metal part?
Multiply the cross-sectional area by the length and then by the material density. In consistent units — area in mm², length in metres, density in kg/m³ — that is m = A × 10⁻⁶ × ρ, and the result is kg/m. For a plate you would normally work per square metre instead: thickness in millimetres × density in kg/m³ ÷ 1000 gives kg/m². There is no lookup involved, which is why a non-standard size is as accurate here as a standard one.
Why is my supplier’s weight chart different from this one?
Almost always the density. Mill charts for steel are usually computed at a nominal 0.2833–0.2836 lb/in³ (about 7,844–7,850 kg/m³) and round the result. We compute from the real specification density for the material you select, so a 304 stainless figure runs about 1.9 % heavier than the carbon steel figure for identical geometry, and our carbon steel figures can differ from a printed chart in the fourth significant figure.
Does weight tell me if a part is strong enough?
No. Weight is a mass property. Strength and stiffness need the second moment of area, the material’s yield strength and the actual load case — none of which weight gives you. The cross-sectional area in these tables is one input to that calculation, not the answer to it.
Why are the default dimensions the same on every page?
So the tables can be compared. If every shape used its own natural size, the mass column would be meaningless across pages — a 200 mm channel and a 6 mm round bar are not comparable. Every page uses the same 25 mm nominal size (the plate page uses 10 mm thickness, since plate is described by thickness), which means the material-comparison table on each page is a genuine like-for-like comparison.
Can I use these figures for a purchase order?
For an estimate, yes. For a contract, no — buy against the mill certificate. Nominal density is not the density of a specific heat of material, and wrought grades vary within the ranges on the density chart. On a handrail the difference is irrelevant; on a 40-tonne fabricated order a 1 % density difference is 400 kg, which is real money and real truck axles.
Where do the densities come from?
Each material entry names the specification it represents — ASTM A36 and EN 10025 for carbon steel, ASTM A240/A276 for the stainless grades, B209/B211/B221 for aluminium, and so on. They are the nominal engineering values those specifications and the standard handbooks publish, not measured values. Where a grade family genuinely varies — cast iron, bearing bronze, PVC — the entry records the spread so the uncertainty is visible rather than hidden.
Related reference data
The metal-weight cluster is the first of three; pipe shares the same method, and the cross-reference tables cover the designations neither cluster owns.
- 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
- Density chart — all materials
Areas computed from closed-form geometry for 10 section types. Densities are nominal specification values, one per material grade. Unit conversions use the definitional constants 25.4 mm/in, 0.3048 m/ft and 0.45359237 kg/lb.
- 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.