Calculate board feet of lumber. Free online board foot calculator with formula, examples, and FAQ for lumber estimation.
A board foot is a unit of measurement for lumber volume. One board foot equals a board that is 1 inch thick, 12 inches wide, and 1 foot long (144 cubic inches). This calculator helps you determine the board footage of lumber for your project.
Board Feet = (Thickness × Width × Length) / 12Thickness and width are measured in inches, length in feet. The formula divides by 12 to convert to board feet. For multiple pieces, multiply the single piece board feet by the quantity. Note: nominal lumber dimensions differ from actual dimensions.
| Input | Output |
|---|---|
| 2"×6"×8 ft, 10 pieces | 8 board ft/piece, 80 board ft total |
| 2"×4"×12 ft, 20 pieces | 8 board ft/piece, 160 board ft total |
| 1"×8"×10 ft, 5 pieces | 6.67 board ft/piece, 33.33 board ft total |