How board feet are calculated
One board foot is 1 inch thick × 12 inches wide × 12 inches long — 144 cubic inches of wood. The formula is thickness × width × length ÷ 12, with length in feet. A 2-inch × 6-inch × 8-foot board is 2 × 6 × 8 ÷ 12 = 8 board feet. Multiply by the number of pieces to get the total.
Board feet are the standard unit for hardwood lumber pricing, so knowing your total board feet lets you compare quotes directly. Remember that you pay for the nominal size before planing; surfaced boards are smaller than listed, and rough lumber may require extra material to machine flat.
Common lumber sizes in board feet
- 1 × 6 × 8 ft: 4 board feet
- 2 × 4 × 8 ft: 5.33 board feet
- 2 × 6 × 8 ft: 8 board feet
- 1 × 12 × 12 ft: 12 board feet