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Lumber Volume Calculator

Timber is traded by the cubic metre. Convert the section in millimetres to metres, then multiply by length and the number of pieces.

Your numbers

Volume

0.2916m³

Result

0.02916

Weight

145.8kg

Formula

Volume = Width ÷ 1000 × Thickness ÷ 1000 × Length × Count

Weight assumes 500 kg/m³. Pine runs 400–500 and oak over 700, so species matters a great deal.

What to enter

InputDefaultAccepted range
Width (mm)The measurement front to back.901 and up
Thickness (mm)How thick one layer is; times the number of layers gives the whole.901 and up
Length (m)The measurement across, side to side.3.60 and up
CountA plain count of items; it often ends up as the denominator.101 and up

Step by step

FormulaVolume = Width ÷ 1000 × Thickness ÷ 1000 × Length × Count
With the default numbersVolume = 90 ÷ 1000 × 90 ÷ 1000 × 3.6 × 10
AnswerVolume = 0.2916 m³

Quick reference table

Results when only Width (mm) changes and everything else stays put.

Width (mm)Volume (m³)Result (m³)Weight (kg)
450.14580.0145872.9
67.50.21870.02187109.4
900.29160.02916145.8
1350.43740.04374218.7
1800.58320.05832291.6

What each result means

ResultAt default values
Volume (m³)The space a solid holds — length cubed.0.2916
Result (m³)What the formula gives back — the answer this page is for.0.02916
Weight (kg)Weight in tonnes; one tonne is 1,000 kg.145.8

Common mistakes

Weight assumes 500 kg/m³. Pine runs 400–500 and oak over 700, so species matters a great deal.

Glossary

Width
The measurement front to back.
Thickness
How thick one layer is; times the number of layers gives the whole.
Length
The measurement across, side to side.
Count
A plain count of items; it often ends up as the denominator.
Volume
The space a solid holds — length cubed.
Result
What the formula gives back — the answer this page is for.
Weight
Weight in tonnes; one tonne is 1,000 kg.

Frequently asked questions

Q. How is Lumber Volume Calculator calculated?

Volume = Width ÷ 1000 × Thickness ÷ 1000 × Length × Count — Timber is traded by the cubic metre. Convert the section in millimetres to metres, then multiply by length and the number of pieces.

Q. Can you walk through an example?

With Width 90mm, Thickness 90mm, Length 3.6m, Count 10, the answer is Volume 0.2916m³.

Q. What do I need to enter?

Enter Width, Thickness, Length, Count. The result recalculates as you type, and an empty box counts as zero.

Q. How much does the answer move if I change a number?

Changing only Width (mm) moves the answer to Width (mm) 45 → Volume (m³) 0.1458 and Width (mm) 180 → Volume (m³) 0.5832. The table below lays out five steps.

Q. How are the numbers rounded?

Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.

Q. Anything to watch out for?

Weight assumes 500 kg/m³. Pine runs 400–500 and oak over 700, so species matters a great deal.

Related calculators

Keep your length units consistent across inputs — mixing centimetres and metres throws results far off.