Calculate board feet of lumber from dimensions and quantity.
A board foot is a standard lumber volume unit: one board foot equals a piece 12 inches wide, 12 inches long, and 1 inch thick. Formula: board feet = (thickness in inches × width in inches × length in feet) ÷ 12, then multiplied by quantity for multiple pieces.
Lumber, especially hardwood, is commonly priced per board foot rather than per linear foot, since board feet accounts for the actual volume of wood regardless of how it's cut — a thick, narrow board and a thin, wide board can contain the same board footage.
Softwood dimensional lumber (like standard 2x4s at the hardware store) is more commonly priced per linear foot or per piece instead, so board feet calculations come up most often with hardwood or specialty lumber purchases.
Ten pieces of 2" × 6" lumber, each 8 feet long: (2 × 6 × 8) ÷ 12 = 8 board feet per piece × 10 pieces = 80 board feet total.
Because board feet measures volume, not just surface area — a thicker board contains proportionally more wood for the same width and length, and the formula reflects that directly.
No — a nominal '2x6' is actually closer to 1.5" × 5.5" after milling and drying. For a precise board-foot calculation, use actual measured dimensions rather than the nominal size printed on the label.
Not typically — plywood and other sheet goods are usually priced per sheet or per square foot, not per board foot, since they're a different product category from dimensional lumber.