Convert board dimensions into board feet, add a waste allowance, and price the whole order.
How this calculator arrives at its answer
A board foot is a volume measure — one square foot of lumber an inch thick. Hardwood is sold this way rather than by length, which is why two boards of the same length can cost very different amounts.
Thickness is measured in quarters at the sawmill: 4/4 is one inch, 8/4 is two inches. Enter the actual thickness in inches and the calculator handles the rest, including a waste allowance for cuts and defects.
The default scenario, worked through
As an example, with a waste allowance of 10%, the calculator returns a total board feet of 40 bf. Underneath, Board feet per board comes out at 4 bf and With waste allowance at 44 bf. Change any field and every figure updates as you type.
Getting your answer
- Enter the thickness, width and length of one board.
- Enter how many boards you need.
- Add a waste allowance and the price per board foot.
Formula reference
board feet = thickness (in) × width (in) × length (ft) ÷ 12
or thickness × width × length all in inches ÷ 144
Frequently asked questions
What is a board foot?
A volume of lumber equal to one square foot at one inch thick — 144 cubic inches.
Should I use nominal or actual dimensions?
Use the actual rough dimensions you are being charged for. Surfaced lumber is smaller than its nominal size but is often still priced at the rough measure.
How much waste should I allow?
Ten percent is a common allowance for straightforward work; allow more for figured stock, short parts or heavy defect.