Materials and their densities

16 materials spanning 11.8× in density. Each entry names the specification its density represents, and links to the weight table for all 10 section shapes.

Density is the only material property that changes a weight calculation. Everything else — strength, stiffness, corrosion resistance, cost — is a different question, and this page does not answer it. What it does answer is the one that decides an order, and it answers it with the specification attached rather than with a bare number.

Density chart, lightest first How these values were chosen

Carbon steel

The 7,850 kg/m³ baseline. Cheapest per tonne, needs protection from corrosion.

Carbon Steel 7,850 kg/m³ ±1 % typical spread

The baseline against which every other metal is compared. Mild and medium carbon steels sit at 7,850 kg/m³ across the usual structural and free-machining grades: A36 plate, 1018 shaft, S275JR section. Carbon content moves density so little over the 0.05–0.60 % range that one figure covers the family, which is why mill weight tables for "steel" almost always assume 7,850 kg/m³ (0.2836 lb/in³). Use this entry when the drawing says "steel" and no grade is called out.

Density: 7,850 kg/m³ = 0.2836 lb/in³ · +0.0 % against carbon steel
Specification: ASTM A36 / AISI 1018 / EN 10025 S275
Equivalents: AISI 1018 · EN 1.0401 · JIS SS400 · GB Q235
Typical uses: Structural sections · Plate and bar stock · Fabricated weldments · Shafts and pins

Caution: Unprotected carbon steel corrodes at roughly 0.1 mm/year in a mild inland atmosphere and far faster in coastal or chemical service, so a corrosion allowance changes the mass you should order — not this density.

Weight tables with this material

Stainless steel

Corrosion-resistant austenitic and ferritic grades, 7,700–8,000 kg/m³.

Stainless Steel 304 8,000 kg/m³ ±1 % typical spread

The default austenitic stainless: 18 % chromium, 8 % nickel, non-magnetic in the annealed condition. At 8,000 kg/m³ it is 1.9 % heavier than carbon steel for an identical section, a difference large enough to matter on fabricated orders and small enough to be routinely forgotten. Machining work-hardens it, so heavy stock removal needs slower speeds and consistent feed than a 304 bar will forgive.

Density: 8,000 kg/m³ = 0.2890 lb/in³ · +1.9 % against carbon steel
Specification: ASTM A240 / A276 (UNS S30400)
Equivalents: EN 1.4301 · JIS SUS304 · GB 06Cr19Ni10
Typical uses: Food and beverage equipment · Architectural handrail and trim · Sanitary tubing · General fasteners

Caution: Austenitic grades become slightly magnetic after cold work (drawn bar, formed tube). A magnet test is therefore not a valid grade check.

Weight tables with this material

Stainless Steel 316 8,000 kg/m³ ±1 % typical spread

Identical density to 304, so weight tables can be shared between them — but not material selection. The 2–3 % molybdenum addition is what buys resistance to chlorides and to the sulphuric and acetic acid environments that pit 304. For a weight take-off the two are interchangeable; for a coastal or process-chemical application they are not, and the substitution is usually made for the wrong reason (availability) without recalculating corrosion allowance.

Density: 8,000 kg/m³ = 0.2890 lb/in³ · +1.9 % against carbon steel
Specification: ASTM A240 / A276 (UNS S31600)
Equivalents: EN 1.4401 · JIS SUS316 · GB 06Cr17Ni12Mo2
Typical uses: Marine and coastal hardware · Pharmaceutical and dairy process plant · Chemical storage and pipework · Pulp and paper

Weight tables with this material

Stainless Steel 316L 8,000 kg/m³ ±1 % typical spread

"L" means low carbon, capped at 0.030 % so that welded joints do not sensitise and lose intergranular corrosion resistance in the heat-affected zone. Density is unchanged from 316 at 8,000 kg/m³, which is convenient: a weight take-off done on 316 never has to be redone when the client insists on 316L for the welds. It is the standard choice for any fabricated stainless vessel or spool that will be welded and then exposed to a corrosive service.

Density: 8,000 kg/m³ = 0.2890 lb/in³ · +1.9 % against carbon steel
Specification: ASTM A240 / A276 (UNS S31603)
Equivalents: EN 1.4404 · JIS SUS316L · GB 022Cr17Ni12Mo2
Typical uses: Welded process pipework · Pressure vessels and tanks · Pharmaceutical clean service · Desalination plant

Caution: Low carbon also means lower annealed strength than 316 (roughly 170 MPa yield vs 205 MPa), so 316L is not a like-for-like structural substitution.

Weight tables with this material

Stainless Steel 430 7,700 kg/m³ ±1 % typical spread

A ferritic straight-chromium grade — 17 % Cr, essentially no nickel — and therefore magnetic. Its 7,700 kg/m³ makes it the lightest of the stainless family here, a 1.9 % saving against 304 and the only stainless that undercuts carbon steel on mass. That, plus a nickel-free price, is why it dominates appliance trim, kitchen splashbacks and interior decorative panels where corrosion demand is mild and a magnet will be used on it anyway.

Density: 7,700 kg/m³ = 0.2782 lb/in³ · -1.9 % against carbon steel
Specification: ASTM A240 (UNS S43000)
Equivalents: EN 1.4016 · JIS SUS430 · GB 10Cr17
Typical uses: Appliance and kitchen panels · Interior decorative trim · Automotive exhaust trim · Elevator cladding

Caution: Ferritic grades have lower ductility and weldability than 304; avoid specifying it for formed or welded structural work.

Weight tables with this material

Aluminium

Roughly one third of steel’s mass, with roughly one third of its stiffness.

Aluminum 6061-T6 2,700 kg/m³ ±1 % typical spread

The general-purpose structural aluminium: magnesium and silicon alloyed, precipitation-hardened to T6, readily welded and machined. At 2,700 kg/m³ it is 2.91 times lighter than carbon steel, which is the entire reason it gets specified — but designers routinely forget that its modulus is also only about a third of steel’s, so a straight aluminium-for-steel swap cuts mass by 66 % while roughly tripling deflection for the same section. Weight savings and stiffness are separate problems.

Density: 2,700 kg/m³ = 0.0975 lb/in³ · -65.6 % against carbon steel
Specification: ASTM B221 / B209 (T6 temper)
Equivalents: EN AW-6061 · JIS A6061 · GB 6061
Typical uses: Aircraft and drone frames · Marine decking and masts · Machine guards and jigs · Truck and trailer bodies

Weight tables with this material

Aluminum 5052-H32 2,680 kg/m³ ±1 % typical spread

The highest-strength common non-heat-treatable alloy and the best of the sheet alloys for marine service, with roughly twice the corrosion resistance of 6061 in salt water. Its 2,680 kg/m³ is marginally below 6061 — a 0.7 % difference, invisible on a take-off but real. It work-hardens rather than age-hardens, so it cannot be strengthened after forming and is normally supplied in H32. Preferred for fuel tanks, hull plate and formed panels that will see chloride.

Density: 2,680 kg/m³ = 0.0968 lb/in³ · -65.9 % against carbon steel
Specification: ASTM B209 (H32 temper)
Equivalents: EN AW-5052 · JIS A5052 · GB 5052
Typical uses: Marine hulls and tanks · Fuel and hydraulic tanks · Sheet metal enclosures · Pressure vessels (low)

Weight tables with this material

Aluminum 7075-T6 2,810 kg/m³ ±1 % typical spread

Zinc-bearing, aerospace-grade and the strongest aluminium in ordinary supply — comparable in strength to some mild steels. It is also the densest aluminium here at 2,810 kg/m³, which is the trade-off nobody mentions: choosing 7075 over 6061 for strength costs 4.1 % more mass for the same volume. Its corrosion resistance is poor without cladding or anodising, and it is generally considered unweldable, so it belongs in machined and riveted parts, not fabricated frames.

Density: 2,810 kg/m³ = 0.1015 lb/in³ · -64.2 % against carbon steel
Specification: ASTM B211 / B209 (T6 temper)
Equivalents: EN AW-7075 · JIS A7075 · GB 7075
Typical uses: Aerospace structural parts · High-load bicycle and motorsport · Moulds and tooling plate · Precision machined fittings

Caution: Not recommended for sustained elevated-temperature service; strength falls off well before 6061’s does.

Weight tables with this material

Copper alloys

Copper, brass and bronze at 8,500–8,940 kg/m³ — heavier than steel.

Copper C11000 8,940 kg/m³ ±1 % typical spread

Electrolytic tough pitch copper, 99.9 % Cu minimum — the electrical conductor standard, and the densest material here after lead at 8,940 kg/m³. That density is the point: high conductivity and high mass travel together in copper, which is why busbar and winding take-offs are always done by mass. It is 13.9 % heavier than carbon steel, so a copper busbar replacing a steel one of the same section gains weight while gaining conductivity.

Density: 8,940 kg/m³ = 0.3230 lb/in³ · +13.9 % against carbon steel
Specification: ASTM B152 / B187 (UNS C11000, ETP)
Equivalents: EN CW004A · JIS C1100 · GB T2
Typical uses: Busbar and windings · Plumbing tube · Heat exchangers · Roofing and flashing

Weight tables with this material

Brass C36000 8,500 kg/m³ ±2 % typical spread

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 · +8.3 % against carbon steel
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

Caution: Lead content (typically 2.5–3.7 %) restricts use in potable water. Typical density range 8,400–8,700 kg/m³ by composition.

Weight tables with this material

Bronze C93200 8,800 kg/m³ ±3 % typical spread

Tin-lead bearing bronze, the standard material for plain bushes and wear plates because its microstructure carries a soft lead phase that acts as a built-in lubricant. At 8,800 kg/m³ it sits between copper and brass, and being a cast alloy its density genuinely varies more than the wrought metals — 8,700 to 9,000 kg/m³ is normal across bronze chemistries, so a take-off on a large cast bush should come from the caster’s certificate, not from a table.

Density: 8,800 kg/m³ = 0.3179 lb/in³ · +12.1 % against carbon steel
Specification: ASTM B505 (UNS C93200, bearing bronze)
Equivalents: SAE 660 · EN CW458K · GB ZQSn6-6-3
Typical uses: Plain bearings and bushes · Worm gears · Pump and valve components · Wear plates

Caution: Cast alloys carry higher density uncertainty than wrought. Typical spread 8,700–9,000 kg/m³.

Weight tables with this material

Other metals

Titanium, cast iron and lead, spanning 4,510 to 11,340 kg/m³.

Titanium Grade 2 4,510 kg/m³ ±1 % typical spread

Commercially pure titanium, the workhorse corrosion grade rather than the aerospace high-strength one. Density 4,510 kg/m³ gives it 57 % of steel’s mass with a comparable tensile strength, which is the headline — but titanium’s real advantage in chemical plant is a passive oxide film that survives chlorides, wet chlorine and oxidising acids that destroy stainless. It is expensive enough that the mass change is a secondary concern to the corrosion allowance it lets you remove.

Density: 4,510 kg/m³ = 0.1629 lb/in³ · -42.5 % against carbon steel
Specification: ASTM B265 / B348 (UNS R50400)
Equivalents: EN 3.7035 · JIS 2H · GB TA2
Typical uses: Chemical process heat exchangers · Desalination and marine · Medical implants · Anodised architectural panels

Caution: Poor machinability — low thermal conductivity causes heat to concentrate at the cutting edge. Titanium is also combustible as fine swarf.

Weight tables with this material

Gray Cast Iron 7,200 kg/m³ ±3 % typical spread

The only common ferrous material lighter than steel, because the graphite flakes that give cast iron its damping and machinability also displace iron — 7,200 kg/m³ against steel’s 7,850, an 8.3 % saving. Those flakes are also why it fails in tension but excels in compression, and why engine blocks, machine bases and drainage products are cast iron. Normal spread is 7,150–7,350 kg/m³, so a large casting should always be weighed against the foundry’s own figure.

Density: 7,200 kg/m³ = 0.2601 lb/in³ · -8.3 % against carbon steel
Specification: ASTM A48 Class 30 / ISO 185
Equivalents: EN GJL-250 · JIS FC250 · GB HT250
Typical uses: Machine tool bases · Engine blocks and manifolds · Drainage and soil pipe · Column and bracket castings

Caution: Density varies with graphite content and section thickness — thin sections cool faster and can differ from a heavy boss in the same casting.

Weight tables with this material

Lead 11,340 kg/m³ ±1 % typical spread

The densest material in the catalogue at 11,340 kg/m³ — 44 % heavier than carbon steel — and used precisely for that. Lead sheet is specified for acoustic and radiation shielding, where the performance metric is mass per unit area, so a sheet weight table is not an incidental output here, it is the design input: 1 mm of lead is about 11.34 kg/m². It is also extremely soft and creeps under sustained load, so it is normally supported, not self-carrying.

Density: 11,340 kg/m³ = 0.4097 lb/in³ · +44.5 % against carbon steel
Specification: ASTM B29 (UNS L50049, chemical lead)
Equivalents: EN PB000 · GB Pb1
Typical uses: Radiation shielding · Acoustic and vibration isolation · Roof flashing and damp courses · Battery plates

Caution: Heavy-metal hazard: machining, welding and dross handling require controls. Creeps under its own weight at ambient temperature.

Weight tables with this material

Polymers

PVC and HDPE, an order of magnitude lighter than steel but far lower strength.

Rigid PVC (Type I) 1,400 kg/m³ ±3 % typical spread

Unplasticised polyvinyl chloride, the standard solvent-welded pipe and duct material. At 1,400 kg/m³ it is 82 % lighter than carbon steel — the single biggest mass saving available in the catalogue — which is why PVC pipe is specified for drainage, irrigation and fume ducting where nothing structural is asked of it. The figure assumes rigid, unplasticised compound; flexible PVC contains plasticiser and runs 1,200–1,500 kg/m³, and foamed PVC is far lower again.

Density: 1,400 kg/m³ = 0.0506 lb/in³ · -82.2 % against carbon steel
Specification: ASTM D1784 Cell Classification 12454
Equivalents: EN PVC-U · JIS PVC · GB PVC-U
Typical uses: Drainage and soil pipe · Irrigation and fume duct · Chemical process pipework · Electrical conduit

Caution: Density is formulation-dependent: rigid compound 1,380–1,450 kg/m³, plasticised grades are lighter and foamed grades much lighter. Strength falls sharply above about 60 °C.

Weight tables with this material

HDPE (PE 100) 960 kg/m³ ±2 % typical spread

High-density polyethylene and the lightest material in the catalogue at 960 kg/m³ — it floats. That is not a curiosity: buoyancy governs how submerged outfall and intake lines are installed, and HDPE’s ability to be towed and floated into place in long strings is why it displaced steel for marine pipelines. It is also tougher than PVC at low temperature and tolerates ground movement without cracking, at the cost of much lower pressure rating at the same wall thickness.

Density: 960 kg/m³ = 0.0347 lb/in³ · -87.8 % against carbon steel
Specification: ISO 4427 / ASTM D3350 (PE 100 black)
Equivalents: EN PE 100 · JIS PE100 · GB PE100
Typical uses: Water and gas mains · Submarine outfall lines · Landfill and leachate pipe · Geomembrane and lining

Caution: Density splits into two families: PE 100 pipe grades 950–960 kg/m³, PE 63/80 grades 930–945 kg/m³. Black compound includes ~2 % carbon black.

Weight tables with this material

Reference data and tools

Every material here is available in the calculators with arbitrary dimensions.

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

Data source and method

One nominal density per material grade, from the specification named in each entry. Where a grade family genuinely varies (cast iron, bearing bronze, PVC, HDPE) the spread is recorded rather than averaged away. Derived fields — lb/in³ and the relative percentage — are computed at build time and never hand-typed.

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.