Board Foot Calculator
A board foot is a volume of wood 12 inches long, 12 inches wide and 1 inch thick (144 cubic inches). Hardwood lumber is priced by the board foot.
The formula
Board feet = thickness (in) × width (in) × length (ft) ÷ 12
Thickness uses the nominal rough size in quarters: 4/4 = 1 inch, 5/4 = 1.25, 6/4 = 1.5, 8/4 = 2, 10/4 = 2.5, 12/4 = 3.
Examples
| Board | Calculation | Board feet |
|---|---|---|
| 4/4 × 6 in × 8 ft | 1 × 6 × 8 ÷ 12 | 4 |
| 8/4 × 8 in × 10 ft | 2 × 8 × 10 ÷ 12 | 13.33 |
| 6/4 × 10 in × 6 ft | 1.5 × 10 × 6 ÷ 12 | 7.5 |
Calculator
Plan for waste
Add 15 to 20 percent to your total for defects, grain matching and milling. Rough boards lose about 1/8 to 1/4 inch per face when planed.