Board Foot Calculator
Tally different lumber sizes in separate rows, keeping actual thickness and width in inches and length in feet. Board feet measure wood volume; this tool does not estimate how many deck boards cover a floor. Optional allowance and price produce a purchasing estimate.
Your result
How the calculation works
Board feet = thickness(in) × width(in) × length(ft) × quantity / 12. Add all sizes, then multiply by 1 + allowance/100. One board foot is 0.002359737216 m³.
Worked example
One actual 1 in × 12 in × 8 ft board contains 8 board feet. At $5 per board foot and no allowance, material cost is $40. Two identical boards contain 16 board feet.
Assumptions and limitations
Dimensions are actual entered sizes. Nominal two-by-four labels are not automatically reduced to dressed dimensions. Allowance is volume-based; it does not optimize stock lengths, kerf or offcuts.
Ask whether your supplier prices nominal, rough or finished dimensions. Add separate rows for different lengths and grades, and confirm delivery, tax and minimum charges.
Sources and editorial responsibility
Maintained by Renvoro Pty Ltd. Sources inform the methods and assumptions shown here; outputs have the limitations described on this page.
Method reviewed 2026-10-13. Calculation standards · Report an issue