How we worked it out
Updated as you change the numbers.
- Board feet per board = thickness (in) × width (in) × length (ft) ÷ 12 = 1 × 6 × 8 ÷ 12 = 4.
- Total = 4 × 10 boards = 40 board feet.
Method and assumptions
One board foot is 144 cubic inches: a board 1 in thick, 12 in wide and 1 ft long. With thickness and width in inches and length in feet, board feet = thickness × width × length ÷ 12.
Hardwood dealers measure rough lumber at its nominal (rough) thickness, so a 4/4 board counts as 1 in even after it is planed thinner. Softwood dimensional lumber (2 × 4s and so on) is usually priced per piece or per linear foot instead.
Tips
- Buy 15 to 30% more board feet than your cut list needs to allow for defects, planing and offcuts.
- For random-width hardwood, measure each board’s width and add them up.
Questions
How many board feet are in a 2 × 4 × 8?
Using nominal size, 2 × 4 × 8 ÷ 12 = 5.33 board feet. Using its actual 1.5 × 3.5 in size, it holds 3.5 board feet of wood.
Sources
Method and figures checked on . Every worked answer on this page is covered by an automated test. Found a mistake? Tell us.