Board Foot Calculator
Board feet of lumber from the number of pieces and their nominal size, per piece and in total, with the lineal feet and the cost.
Board feet
80 bd ft
8 per piece · cost 100.00
- Board feet
- 80 bd ft
- Per piece
- 8 bd ft
- Lineal feet
- 80' 0"
- Nominal volumefor comparing with a metric price
- 0.1888 m³
- Cost
- 100.00
Kalku is coming to iPhone and Android
Kalku has board feet as a unit on its keypad, so a length × width × thickness converts in one tap, and framing calcs for studs, joists, decks, fences and lumber cost. It works with no signal at the yard and saves every order to share as a PDF.
How it is worked out
A board foot is 144 cubic inches of lumber at its nominal size. Multiply the nominal thickness, the nominal width and the length, all in inches, divide by 144, and multiply by the number of pieces. The cost is the board feet times the price per board foot. The lineal feet are the pieces times the length, and the nominal volume in cubic metres is there for comparing with a metric price list. This is the Kalku app's Board Feet calc.
Worked example: ten 8 ft 2x6s
- One piece: 2 × 6 × 96 ÷ 144 = 8 board feet.
- Ten pieces: 80 board feet, and 80 lineal feet.
- At 1.25 a board foot: 100.
Board feet in common sizes
| Nominal size | Per foot of length | One 8 ft piece |
|---|---|---|
| 1x4 | 0.333 | 2.67 |
| 1x6 | 0.5 | 4 |
| 2x4 | 0.667 | 5.33 |
| 2x6 | 1 | 8 |
| 2x8 | 1.333 | 10.67 |
| 2x10 | 1.667 | 13.33 |
| 2x12 | 2 | 16 |
| 4x4 | 1.333 | 10.67 |
Questions
What is a board foot?
A volume of wood: 144 cubic inches, a board 1 inch thick, 12 inches wide and 12 inches long. Board feet = thickness × width × length in inches ÷ 144. An 8 foot 2x6 is 2 × 6 × 96 ÷ 144 = 8 board feet.
Nominal or actual size?
Nominal. Lumber is sold by its nominal size, so a 2x6 counts as 2 by 6 inches even though it measures about 1-1/2 by 5-1/2 once dried and planed. Enter the name of the size, not what the tape says.
How is hardwood measured?
Rough hardwood is sold by the board foot on its rough thickness, in quarters of an inch: 4/4 is 1 inch, 6/4 is 1-1/2, 8/4 is 2. Enter 1, 1.5 or 2 as the thickness. A 10 foot 4/4 board 8 inches wide is 6.67 board feet.
Board feet or lineal feet?
Lineal feet is just the length, whatever the size of the piece, and is how dimension lumber is often priced. Board feet accounts for the size, which is how hardwood and large orders are priced. The calculator gives both.
