Board Feet Calculator
Convert lumber dimensions to board feet (BF), traditional US unit: 1 BF = 144 cubic inches (12"×12"×1").
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Board feet: the US standard for lumber volume
One board foot (BF) is 144 in³, which is what you get from a board measuring 1 ft × 1 ft × 1 in thick. The math is BF = (thickness in × width in × length ft) / 12. Take a 2 in × 6 in × 8 ft board: (2·6·8)/12 lands at 8 BF. Brazil works in cubic meters instead, and 1 m³ ≈ 424 BF. American sawmills price by BF, while here you buy by m³ or by the piece. That gap matters the moment you import American hardwoods like oak, maple, walnut or cherry for fine carpentry and lutherie, since the supplier's quote comes back in BF.
Applications
Fine carpentry built from imported hardwoods. Oak/maple/walnut imports coming out of the US and Canada. Custom furniture ordered through international suppliers. And musical instrument lutherie, where guitars, violins and basses run on maple, spruce and mahogany sold by the board foot. You'll also see BF on commercial quotes for hardwood flooring and decking brought in from the US.
FAQ
How do I convert BF to m³? Divide the BF figure by 424, since 1 m³ ≈ 424 BF. So 100 BF works out to 100/424 ≈ 0.236 m³.
Does thickness in mm work? Not directly. Convert to inches first, where 1 in = 25.4 mm. The BF formula expects thickness and width in inches and length in feet.
Why does the US use board feet? It goes back to colonial sawmills, where a 1 ft × 1 ft × 1 in slab was the thing people traded. The habit stuck, and the whole American chain from sawmills to distributors to retail still quotes in BF.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.