Sixteenth
Board Foot Calculator
Add each board by thickness, width and length. You get the board feet for each line, the total, and the cost when you enter a price per board foot.
Nominal sizes: a 2×6 is 2 by 6. For hardwood type quarters like 8/4. Length in feet, or 96 in, or 8' 6".
The board foot formula
A board foot is a piece of wood 12" × 12" × 1" thick, which is 144 cubic inches. Lumber yards price hardwood and many large timbers by the board foot.
board feet = thickness (in) × width (in) × length (ft) ÷ 12
For example, ten 2×8s that are 12' long: 2 × 8 × 12 ÷ 12 = 16 board feet each, 160 board feet in all.
Board feet for common sizes, per foot of length
| Size | Board feet per foot | 8' board | 12' board | 16' board |
|---|---|---|---|---|
| 1×6 | 0.5 | 4 | 6 | 8 |
| 2×4 | 0.667 | 5.33 | 8 | 10.67 |
| 2×6 | 1 | 8 | 12 | 16 |
| 2×8 | 1.333 | 10.67 | 16 | 21.33 |
| 2×10 | 1.667 | 13.33 | 20 | 26.67 |
| 2×12 | 2 | 16 | 24 | 32 |
| 4×4 | 1.333 | 10.67 | 16 | 21.33 |
| 6×6 | 3 | 24 | 36 | 48 |
Questions
How do you calculate board feet?
Board feet = thickness (in) × width (in) × length (ft) ÷ 12. One board foot is 144 cubic inches, such as a board 1" thick, 12" wide and 1' long. A 2×6 that is 8' long is 2 × 6 × 8 ÷ 12 = 8 board feet.
Do I use nominal or actual size?
Lumber yards price softwood dimensional lumber by its nominal size (a 2×4 counts as 2" × 4"). Rough hardwood is sold by its rough thickness in quarters: 4/4 is 1", 5/4 is 1-1/4", 8/4 is 2". You can type 8/4 in the thickness box.
How many board feet are in a 2×4×8?
2 × 4 × 8 ÷ 12 = 5.33 board feet.