Calculate board feet of lumber from the thickness, width, length, and quantity — and the total cost at a price per board foot.
A board foot is 144 cubic inches of lumber. Use nominal dimensions unless the seller prices by actual (surfaced) size. Estimate only.
A board foot is the standard unit for hardwood lumber — one square foot at one inch thick, or 144 cubic inches. Multiply thickness × width (inches) × length (feet) and divide by 12 to get board feet per board.
Board feet = thickness(in) × width(in) × length(ft) ÷ 12
Rough lumber is usually priced by nominal size; surfaced (S4S) lumber may be priced by actual dimensions. Ask the supplier which they use.
A linear foot only measures length; a board foot measures volume, so it accounts for thickness and width too.
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