Board Foot Calculator (Board Feet & Total Cost)

Convert a board's thickness, width, and length into board feet per board and for the whole stack, plus a running cost at your price per board foot.

Inputs
in
in
ft
boards
$
Results update as you type — no submit
ResultsLIVE
Total board feet
40 bd ft
≈ 3.33 cu ft (0.09 m³)
Total cost
$130.00
$13.00 per board
Total cost$130.00
Per board4 bd ft
Volume3.33 cu ft (0.09 m³)
Formula
per board = (1 × 6 × 8) ÷ 12 = 4 bd ft
total = 4 × 10 = 40 bd ft · cost = 40 × $3.25 = $130.00
Diagram — board face & endNTS
8′6″1″FACE VIEW + END · NOMINAL SIZEMEASURESHED10 × 1″ × 6″ × 8′40 BD FT
MeasureShedmeasureshed.com/calculator/board-foot-calculator
Board feet — material listUNITS: IN/FT · NOMINAL SIZE
Inputs
Board size (T × W × L)1″ × 6″ × 8′
Quantity10
Price$3.25/bd ft
Results
Total board feet40 bd ft
Per board4 bd ft
Volume3.33 cu ft
Total cost$130.00
Board face & endNTS
8′6″1″FACE VIEW + END · NOMINAL SIZEMEASURESHED10 × 1″ × 6″ × 8′40 BD FT
Shopping list
☐ 10 × 1″ × 6″ × 8′ = 40 bd ft ($130.00)
Formula
per board = (1 × 6 × 8) ÷ 12 = 4 bd ft
total = 4 × 10 = 40 bd ft
cost = 40 × $3.25 = $130.00
Estimates for planning only — verify before purchaseSHEET 1 OF 1

How it works

Rough and hardwood lumber is sold by the board foot, a measure of volume rather than length. One board foot is the wood in a piece a foot square and an inch thick — 144 cubic inches. To find the board feet in any board, multiply its nominal thickness in inches by its width in inches by its length in feet, then divide by 12. The divide-by-twelve reconciles the mixed units: thickness and width are counted in inches while length is in feet, so dividing brings everything into the same measure.

Because board feet describe volume, a thick or wide board holds far more than a thin one of the same length. A 1 in by 6 in board and a 2 in by 12 in board of equal length are worlds apart on the invoice. This calculator works out the board feet in a single piece, multiplies by the quantity you plan to buy, and — if you enter a price per board foot — shows the running cost so you can compare quotes without a spreadsheet.

The result is the same whether you think in inches and feet or in millimetres and metres. Internally the tool converts your entries to a volume, so the metric readout shows the equivalent cubic feet and cubic metres beside the board-foot total. Purchasable board feet are shown to the hundredth; lumberyards round the charge their own way, so treat the cost as an estimate.

Worked example
10 boards · 1 in × 6 in × 8 ft · $3.25 per board foot
per board = (1 × 6 × 8) ÷ 12 = 4 board feet
total = 4 × 10 = 40 board feet → 40 × $3.25 = $130.00

Questions about board feet

A board foot is a volume of lumber equal to a piece 1 ft long, 1 ft wide, and 1 in thick — 144 cubic inches, or one twelfth of a cubic foot. Rough and hardwood lumber is priced this way because the measure captures thickness, width, and length at once, unlike a plain length count.

SOURCES — NIST Handbook 130-2026, Uniform Regulation for the Method of Sale of Commodities, §2.12.1.1 ("A board foot is the volume of a board 1 ft long, 1 ft wide, and 1 in thick or its equivalent (144 in³ of wood)"; §2.12.3.2–2.12.3.3 give the nominal vs. minimum-surfaced hardwood sizes and §2.12.4.1 the net-board-footage invoicing rule.) · Voluntary Product Standard PS 20-25, American Softwood Lumber Standard (NIST / U.S. Department of Commerce, January 2025), §2.2 and §3.4.4 (board measure is nominal thickness in inches × nominal width in feet × length in feet (the divide-by-12 rule), and "no inferences shall be drawn that the 'nominal' sizes are dressed sizes.") · NIST Special Publication 811, 2008 edition, Appendix B §B.6 and §B.8 (since 1959 the yard has been "defined as exactly equal to 0.9144 m", and the §B.8 entry inch (in) → meter (m) 2.54 E−02 is boldface ("a factor in boldface is exact"), which fixes 144 in³ = 0.002359737216 m³ for the metric readout.)
Estimates for planning only — verify before purchase

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