calcs.homes
calcs.homes
Enter your lumber's thickness, width, and length to get total board feet and cost — switch to EU for cubic meters, the metric equivalent used for lumber pricing outside North America.
Estimate only — mill tally and grade can shift actual footage and price.
One board foot equals 144 cubic inches — a nominal 1 in × 12 in × 12 in piece — so the formula is (thickness in × width in × length ft) ÷ 12, multiplied by quantity for a full order's total. In metric, we skip board feet entirely and compute cubic meters directly: (thickness mm ÷ 1000) × (width mm ÷ 1000) × length m × quantity.
Board feet exists because lumber pricing needs a volume unit, not just a length or area one — a 2x10 and a 2x4 of the same length contain very different amounts of wood, which board feet captures where linear or square footage can't. It's the unit sawmills, lumberyards, and hardwood suppliers price by across North America; outside that market, cubic meters serve the same purpose, which is why switching the toggle changes the underlying formula rather than just relabeling the same number.
Multiply thickness (in) × width (in) × length (ft), then divide by 12. A 2x6 that's 8 ft long is (2 × 6 × 8) ÷ 12 = 8 board feet.
No — board foot is a volume measurement that includes thickness, while square footage is only area. A thicker board has more board feet for the same footprint.