Enter a board's thickness, width, and length to convert it into board feet, the standard unit lumber is bought and sold by.
How to Use the Board Foot Calculator
Thickness and width go in inches, length in feet, and quantity is however many identical pieces you're pricing or ordering.
A board foot is a volume, not a length — one board foot is a piece 12 inches wide, 12 inches long, and 1 inch thick, or any combination that multiplies out to the same volume. It's the unit hardwood and most milled lumber gets priced by, instead of linear feet, precisely because a 2×10 and a 1×4 of the same length aren't the same amount of wood.
board feet = thickness (in) × width (in) × length (ft) ÷ 12That ÷12 is doing the unit conversion between the length-in-feet input and the inch-based thickness and width — it's easy to drop when doing this by hand, which is the most common board-foot math mistake. Multiply the per-piece result by quantity and you've got the total for the whole order.