Calculator
Board Foot Calculator
Estimate lumber/timber volume from thickness, width, length, and quantity. Use it when comparing boards, planning material purchases, or checking rough stock requirements before a project.
Board foot calculator
Result
Enter dimensions, then calculate to see board feet and volume.
These results are estimates only. Verify measurements, material specifications, structural requirements, safety requirements, and local building rules before buying materials or building.
How this calculator works
Board feet are a volume measurement often used when buying rough lumber/timber. The calculator accepts metric or imperial dimensions, converts them to a common volume, and reports board feet plus the approximate cubic metre equivalent.
Use the optional price field when stock is priced per board foot. The currency symbol is displayed exactly as entered and no exchange-rate conversion is performed.
Formula
- Imperial formula: board feet = thickness_inches x width_inches x length_feet x quantity / 12.
- Alternative volume formula: board feet = cubic_inches / 144.
- Metric route: calculate cubic metres, then convert with 1 cubic metre = 423.776 board feet.
Worked example
For five boards at 2 inches thick, 8 inches wide, and 10 feet long: 2 x 8 x 10 x 5 / 12 = 66.67 board feet.
The approximate volume is 66.67 x 0.00235974 = 0.157 cubic metres.
Common mistakes
- Using nominal dimensions when the actual board is smaller.
- Entering length in inches but treating it as feet.
- Forgetting quantity or waste when buying rough or defect-prone stock.
- Comparing prices without checking whether the supplier uses board feet, linear length, or piece pricing.
FAQs
Can I use metric dimensions for board feet?
Yes. The calculator converts metric dimensions to volume and then estimates board feet.
What does one board foot mean?
One board foot is 1 foot by 1 foot by 1 inch, or 144 cubic inches.
Does board foot pricing include waste?
Not automatically. Add extra material for defects, milling loss, grain selection, and cutting mistakes.
Should I use nominal or actual dimensions?
Use actual dimensions whenever you need a realistic material quantity or cost estimate.
Calculator disclaimer
These results are estimates only. Verify measurements, material specifications, structural requirements, safety requirements, and local building rules before buying materials or building.