Board Foot Calculator
Calculate sawn-lumber volume from thickness, width, length and piece count. Get board feet, metric volume and a cost estimate without rounding each board prematurely.
Changing a unit selector reinterprets the numbers; it does not convert your entries. Update the inputs before calculating. Prices are examples in your own currency.
Board foot formula
A board foot is 144 cubic inches: a piece 12 inches wide, 12 inches long and 1 inch thick. With width and thickness in inches and length in feet, multiply thickness × width × length ÷ 12. Multiply by the number of identical pieces. One cubic foot contains 12 board feet.
Worked example
Ten boards measuring 2 inches × 6 inches × 8 feet each contain 8 board feet per piece and 80 board feet in total. A 10% allowance gives an 88-board-foot budget. At 5 per board foot, the net cost is 400 and the budget with allowance is 440 in your currency.
Should I use actual or nominal sizes?
The result uses exactly the dimensions you enter. Use actual dimensions when estimating physical volume. For a supplier quote, use the supplier’s billing convention; rough-sawn thickness, nominal sizes and tally rounding can differ from dressed dimensions. Ask the supplier before comparing invoices. This calculator does not apply NHLA grading or tally-rounding rules.
Is this a log or linear-foot calculator?
No. Logs need a log-scaling method and assumptions about sawmill recovery. A linear foot describes length only; board feet describe volume. This tool also does not decide strength, species suitability or beam spans. For a mixed-size order, calculate each size separately and sum the net board feet before applying a common allowance.
Definition and formula: American Hardwood Export Council measurement guide.
Continue planning your project
Deck Board Calculator · Stair Stringer Calculator
Reviewed 5 November 2026. Free, no signup. Calculations run in your browser. Confirm measurements and product specifications before ordering. Costs exclude labour, tax and delivery.