Board foot calculator
A board foot is a volume: 144 cubic inches of lumber, or one piece 1 inch thick by 12 inches wide by 1 foot long. It is how rough and hardwood stock is priced, and it lets you compare a quote on 2×10s against a quote on 2×12s without doing it in your head.
Prices move weekly and by region. Enter the unit price your yard quoted you — the defaults are round placeholders, not a market average.
Nominal, not actual — and that is correct
The one thing that confuses people: board feet use the nominal size. A 2×4 counts as two by four even though it measures about 1½ by 3½. That is not an error, it is the convention the whole trade prices on — the missing volume went to the planer, and everyone's quote assumes it.
So when you compare two quotes in dollars per board foot, they are comparing like with like. Convert to actual dimensions on one side and the comparison breaks.
Worked example
One 2×10 at 12 feet is 20 board feet. Ten of them are 200. At whatever your yard charges per board foot, that is your joist package before waste.
| Size | Board feet in 12 ft |
|---|---|
| 2x6 | 12 |
| 2x8 | 16 |
| 2x10 | 20 |
| 2x12 | 24 |
| 4x4 | 16 |
| 6x6 | 36 |
When to use it and when not to
Use it for rough and hardwood stock, for comparing quotes across sizes, and for pricing a framing package where the yard quotes per board foot.
Do not use it for decking. Deck boards are sold by the piece or by the linear foot, and converting them to board feet only adds a step — that is what the board calculator is for. Sheet goods are priced by the sheet, and hardware by the box.
One trap on hardwood: it is often sold in quarter thicknesses — 4/4 is one inch nominal, 8/4 is two. Convert to the nominal inch before entering it here, and remember that surfaced stock is thinner than its quarter number while still being priced on it.
Sources
Nothing here is asserted as a current figure. The tool is arithmetic on what you type, and every default is a round placeholder for your yard's quote.