Wood Volume Calculator: Cubic Feet, Cubic Metres and Board Feet
Multiply length by width by thickness to get a board’s volume, then convert to whichever unit you need — cubic feet and board feet for imperial measurements (1,728 cubic inches per cubic foot, 12 board feet per cubic foot), or cubic metres for metric timber — switch modes below and enter your dimensions for an instant result.
Quick Answer
Multiply length by width by thickness to get a board’s volume, then convert to whichever unit you need — cubic feet and board feet for imperial measurements (1,728 cubic inches per cubic foot, 12 board feet per cubic foot), or cubic metres for metric timber — switch modes below and enter your dimensions for an instant result.
Wood Volume Calculator: Cubic Feet, Cubic Metres and Board Feet
Enter your values below for an instant result, then see the formula, worked example, and common mistakes.
Enter your board dimensions, then click calculate.
How to Use This Calculator
Use inches for imperial lumber (gives board feet and cubic feet); use millimetres for metric timber (gives cubic metres).
These are the three dimensions of your board or piece of stock — for imperial mode all three go in inches; for metric mode all three go in millimetres.
If you have multiple identical pieces, entering a quantity multiplies the per-piece volume into a running total.
Board feet is the standard hardwood pricing unit in the US; cubic feet is useful for shipping/storage volume; cubic metres is the standard for most of the world’s metric timber trade.
Formula
Volume = Length x Width x Thickness (all three dimensions in the same unit). For imperial: Cubic feet = (L x W x T in inches) / 1,728, since 1 cubic foot = 1,728 cubic inches. Board feet = (Thickness x Width x Length in feet) / 12. For metric: Cubic metres = Length(m) x Width(m) x Thickness(m) directly, with no extra conversion factor needed.
Reference Table: Volume Unit Conversions
| Convert from | Convert to | Multiply/divide by |
|---|---|---|
| Cubic inches | Cubic feet | Divide by 1,728 |
| Board feet | Cubic feet | Divide by 12 |
| Cubic feet | Board feet | Multiply by 12 |
| Cubic metres | Cubic feet | Multiply by ~35.31 |
| Cubic feet | Cubic metres | Multiply by ~0.0283 |
Common Mistakes to Avoid
- Mixing unit systems within one calculation — entering some dimensions in inches and others in millimetres will give a meaningless result; always convert everything to one unit system first.
- Confusing board feet (a volume measurement including thickness) with square feet (an area measurement that ignores thickness) — they are not interchangeable for pricing or ordering purposes.
- Forgetting to multiply by quantity when calculating total volume for a full order of multiple identical pieces.
- Using nominal (pre-milling) lumber dimensions when the actual finished size is different — for the most accurate volume, measure actual thickness and width where possible, especially for hardwood.
When the Estimate May Be Wrong
This calculator assumes rectangular (dimensional) stock. For irregular shapes, rough-sawn boards with waney edges, or round logs, actual usable volume will differ from a simple length x width x thickness calculation — log volume in particular requires a specialized log scale rule (like Doyle or International 1/4-inch) rather than this simple rectangular formula.
FAQs
How do you calculate the volume of a piece of wood?
Multiply length by width by thickness, with all three dimensions in the same unit — the result is a volume, which can then be converted to cubic feet, cubic metres, or board feet as needed.
How many board feet are in a cubic foot?
Exactly 12 board feet equal one cubic foot of wood.
How do I convert cubic feet to cubic metres?
Multiply cubic feet by approximately 0.0283 to get cubic metres, or multiply cubic metres by approximately 35.31 to get cubic feet.
Does this calculator work for metric timber sizes?
Yes — switch the unit selector to millimetres/metres mode to enter metric dimensions and get a result directly in cubic metres.
Sources and Methodology
Volume conversion factors (1,728 cubic inches per cubic foot, 12 board feet per cubic foot, ~35.31 cubic feet per cubic metre) are standard, universally recognized unit conversion constants, confirmed against Wikipedia’s Board Foot reference and standard engineering unit conversion tables.
