CalcCommonsHow to use
Enter thickness and width in one unit, then length in its own unit. Set the count of identical boards. Confirm the seller’s measurement convention before using a price per board foot.
For related tasks, try the Volume Calculator.
Formula & how it works
One board foot = 144 cubic inches = 1/12 cubic foot. Board feet = thickness(in) × width(in) × length(ft) ÷ 12 × quantity. Apply allowance to total board feet before estimating cost.
Worked examples
Example 1
Ten boards measuring 1 in × 6 in × 8 ft contain 4 board feet each, or 40 board feet total. A 10% allowance gives 44 board feet. At $5 per board foot, the estimate is $220.
Example 2
One 25.4 mm × 152.4 mm × 2.4384 m board is the same volume as 1 in × 6 in × 8 ft: 4 board feet. Enter its section as 2.54 × 15.24 cm and length as 2.4384 m.
Assumptions & practical notes
A board foot measures volume, not length or surface area. It is not interchangeable with a linear foot.
For hardwood sold as 4/4 or 8/4 rough stock, enter the supplier’s stated billable thickness as 1 or 2 inches. Do not enter a fraction string; use a decimal.
Nominal and actual dimensions differ for many products. The calculator uses exactly what you enter and does not choose a grading or pricing rule.
See our calculation methodology for unit definitions and testing practices.
Results are estimates for planning purposes. Verify measurements, product specifications, and applicable building codes before purchasing materials or starting work.
References & measurement guidance
Use the instructions for your selected product and the requirements that apply to your project. Example inputs are not universal specifications.
Frequently asked questions
Is one board foot the same as one square foot?
Only for a board exactly 1 inch thick. Board feet measure volume; square feet measure area.
Should I use nominal or actual dimensions?
Use the dimensions the seller uses for billing when estimating price. Use measured dimensions when estimating physical volume. Ask the supplier which convention applies.
Can I enter different board sizes?
This calculation handles a batch of identical boards. Calculate each size separately and add the totals.
Does the allowance calculate a cut list?
No. It increases the estimated volume. Knots, grain selection and required part lengths can affect how much usable lumber you need.
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