Board Foot Calculator
A board foot is a volume measure: 144 cubic inches of wood, the same as a piece 1 inch thick, 12 inches wide and 1 foot long. Enter your board's dimensions to get board feet, and add a price per board foot if you want a cost.
Hardwood dealers usually price rough lumber by its nominal (quarter) thickness — 4/4, 5/4, 8/4 — even after surfacing makes the actual board thinner. Use the nominal thickness when you're matching a dealer's pricing, and the actual measurements when you're figuring what a project needs.
How this is calculated
Board feet = (thickness in inches × width in inches × length in feet) ÷ 12, multiplied by the number of boards.
If you enter length in inches, the calculator divides it by 12 first. Cost is board feet × your price per board foot.
Common questions
What is a board foot?
A volume unit for lumber: 144 cubic inches of wood. A board 1" thick, 12" wide and 12" long is exactly one board foot.
Is a board foot the same as a linear foot?
No. A linear foot only measures length. A board foot accounts for thickness and width too, so two boards of the same length can have very different board footage.
What does 4/4 or 8/4 mean?
Hardwood thickness in quarters of an inch. 4/4 is 1 inch nominal, 8/4 is 2 inches. Dealers typically price rough stock by these nominal thicknesses.
Should I buy extra?
Usually yes. Defects, checking and mistakes eat into usable stock. How much extra depends on the wood grade and your cut list, so there is no single right percentage.