Material Weight Calculator

Mass of a bar, plate or tube from its section dimensions and the density of the material. Works the same way for steel, aluminium, plastics and timber — pick the material, pick the section, enter the millimetres.

MaterialDensity 7.85 g/cm³ (7850 kg/m³).

Section

Solid circle — diameter d

Diameter (mm)Measure with a caliper, not by eye

Length (mm)

QuantityFor a total across several identical pieces.

Weight per pieceCarbon Steel

2.466 kg

5.437 lb total · 2.466 kg per metre · cross-section 314.16 mm²

Where that number comes from

check the arithmetic before you quote it

Cross-section area	314.1593 mm²
Volume	314,159 mm³ = 314.1593 cm³
Density	7.85 g/cm³
Mass	314.1593 × 7.85 ÷ 1000 = 2.466 kg

Area × length gives a volume in mm³; dividing by 1000 converts to cm³, and multiplying by the density in g/cm³ gives grams. The figure is geometric — it assumes a solid section of uniform density. Threads, knurling, holes and tolerances all pull the real weight below it, so treat the result as an estimate for quoting and logistics rather than a guaranteed mass.

Same section in other materials

Solid circle — diameter d, 1,000 mm long

Material	Family	Density	Mass	vs steel
Balsa	Wood	0.16	0.0503 kg	0.020×
Cedar (Western Red)	Wood	0.37	0.1162 kg	0.047×
Poplar (Yellow)	Wood	0.42	0.1319 kg	0.054×
Basswood	Wood	0.42	0.1319 kg	0.054×
Redwood	Wood	0.42	0.1319 kg	0.054×
Spruce (Sitka)	Wood	0.43	0.1351 kg	0.055×
Cedar (Eastern Red)	Wood	0.47	0.1477 kg	0.060×
Hemlock (Western)	Wood	0.47	0.1477 kg	0.060×
Cypress (Bald)	Wood	0.48	0.1508 kg	0.061×
Fir (Douglas)	Wood	0.53	0.1665 kg	0.068×
Pine (Southern Yellow)	Wood	0.55	0.1728 kg	0.070×
Mahogany (Honduran)	Wood	0.55	0.1728 kg	0.070×
Cherry (Black)	Wood	0.56	0.1759 kg	0.071×
Larch	Wood	0.58	0.1822 kg	0.074×
Teak	Wood	0.63	0.1979 kg	0.080×
OSB (Oriented Strand Board)	Wood	0.65	0.2042 kg	0.083×
Walnut (Black)	Wood	0.66	0.2073 kg	0.084×
Ash (White)	Wood	0.67	0.2105 kg	0.085×
Birch Plywood	Wood	0.68	0.2136 kg	0.087×
Birch (Yellow Birch)	Wood	0.69	0.2168 kg	0.088×
Bamboo	Wood	0.7	0.2199 kg	0.089×
Maple (Hard Maple)	Wood	0.705	0.2215 kg	0.090×
Beech (American)	Wood	0.72	0.2262 kg	0.092×
Oak	Wood	0.75	0.2356 kg	0.096×
MDF (Medium Density Fibreboard)	Wood	0.75	0.2356 kg	0.096×
Hickory	Wood	0.82	0.2576 kg	0.104×
Rosewood (East Indian)	Wood	0.85	0.2670 kg	0.108×
Ipe	Wood	1	0.3142 kg	0.127×
Nylon (PA 6.6)	Plastics	1.14	0.3581 kg	0.145×
Aluminium	Metals	2.7	0.8482 kg	0.344×
Titanium	Metals	4.51	1.417 kg	0.575×
Carbon Steel	Metals	7.85	2.466 kg	1.000×
Alloy Steel	Metals	7.85	2.466 kg	1.000×
Stainless Steel A2 (304)	Metals	7.9	2.482 kg	1.006×
Stainless Steel A4 (316)	Metals	8	2.513 kg	1.019×
Brass	Metals	8.5	2.670 kg	1.083×

The ratio column compares each material against the section in carbon steel. Aluminium comes out at about a third and oak at about a tenth — which is the whole reason the density figure matters when a part has to be lifted or shipped.

Getting the dimensions right

Hexagon across flats

The area of a hexagon bar is (√3/2)·s² only when s is the width across the flats. Feeding in the corner-to-corner figure makes the answer about 15% too heavy, which is the most common way this calculation goes wrong.

Pipe vs tube

Both are calculated from outside and inside diameter. Nominal pipe size is not a diameter — a 1 inch pipe does not measure 1 inch anywhere. Measure the actual OD and ID, or look up the schedule.

Wood and moisture

Timber is quoted at about 12% moisture content. Green stock can be half as heavy again, and it loses that water after installation — so a weight calculated here is a dried-state figure, not a site-delivery one.

Section formulas used

exact geometry, no lookup tables

Section	Area (mm²)	Notes
Round bar	π · (d/2)²	d = outside diameter
Square bar	a²	a = side length
Hexagon bar	(√3 / 2) · s²	s = width across flats
Flat bar / plate	w · t	w = width, t = thickness
Tube / pipe	(π / 4) · (D² − d²)	D = outside, d = inside diameter

Mass = area × length ÷ 1000 × density, with length in mm and density in g/cm³, giving kilograms. Every figure above is exact for the ideal section; real stock is rolled to a tolerance, so treat the result as an estimate.

Densities used

All 36 materials

Wood values are for air-dried stock at about 12% moisture content. Metal values are typical for the alloy at room temperature; a specific grade from a mill certificate may differ in the third decimal.