Woodworking calculator
Lumber Cost Calculator
Lumber is quoted three different ways depending on the supplier: priced per board foot for most hardwood, per linear foot for trim and dimensional stock, or as a flat price per piece. Pick the basis your yard uses, enter the dimensions and the unit price, and this calculator returns the billable quantity and the total cost.
How it works
When lumber is priced per board foot, the cost depends on volume, so the calculator first works out board feet from thickness, width, and length, then multiplies by your price per board foot. This is how hardwood is almost always sold, which is why two boards of the same length can cost very different amounts when one is thicker or wider.
When lumber is priced per linear foot, only the running length matters, so the calculator multiplies the length in feet by the number of pieces and by the price per foot. Per-piece pricing is the simplest case: it just multiplies the count of boards by the flat unit price.
Matching the basis to the way the board is actually quoted is what keeps an estimate honest. A price that looks cheap per linear foot can be expensive per board foot once thickness and width are taken into account, and the board foot view is the fair way to compare boards of different sizes.
Worked example
Five 4/4 boards, 6 in wide and 8 ft long, at $5.50 per board foot: each is 4 board feet, so 20 board feet at $5.50 = $110.00.
Frequently asked questions
How is lumber usually priced?
Most hardwood is priced per board foot, a measure of volume. Softwood trim and dimensional lumber are often priced per linear foot, and small or specialty pieces may carry a flat per-piece price.
Why does board foot pricing change with thickness?
Board feet measure volume, so a thicker or wider board contains more wood and costs more even at the same length. That is why hardwood is sold by the board foot rather than by length alone.
How do I compare two boards priced differently?
Convert both to a price per board foot. A board priced per linear foot can be re-figured into board feet from its thickness and width, which lets you compare boards of different sizes fairly.
Does this include waste or surfacing charges?
No. The calculator gives the raw material cost. Add an allowance for waste, defects, and any surfacing or planing fees your supplier charges on top of the per board foot price.
What is a linear foot?
A linear foot is simply one foot of length, regardless of width or thickness. Pricing per linear foot is common for moulding and trim where the cross section is fixed and only length varies.
Related calculators
Sources
These calculators are for planning and estimation. Engineering results (shelf sag, wood movement) use published average material properties; real boards vary by grade, grain, moisture and defects. Verify load-bearing designs with a professional.