Board Foot Calculator
A board foot is thickness (in) × width (in) × length (ft) ÷ 12. Enter your board size and quantity to get the total board feet and lumber cost.
How to calculate board feet
Multiply thickness in inches × width in inches × length in feet, then divide by 12. One board foot equals a 1×12 board one foot long. Set the quantity to total a whole stack of identical boards.
Why lumber is priced this way
Hardwood comes in random widths and lengths, so sellers price by volume — the board foot — not by the piece. Knowing your board-foot total lets you compare prices across suppliers and species.
Related measures
For trim and material sold by running length, use the linear feet calculator. For floor and wall coverage, start with the square footage calculator.
Frequently asked
What is a board foot?
A board foot is a volume of lumber equal to a 1-inch-thick, 12-inch-wide, 1-foot-long board — 144 cubic inches. It is how hardwood lumber is priced.
How do I calculate board feet?
Multiply thickness in inches × width in inches × length in feet, then divide by 12. A 1×6 board that is 8 feet long is 4 board feet.
Do I use nominal or actual dimensions?
Hardwood is usually sold by its rough nominal size, so use the nominal thickness and width. Surfaced lumber may measure slightly less.