How to use this calculator
Enter the dimension basis used by your lumber supplier and the number of identical boards. Board feet describe volume: one board foot is 144 cubic inches. Use actual dimensions for physical volume, or the supplier’s tally dimensions for pricing.
The formula
A worked example
A 1 inch × 6 inch × 8 ft board contains 4 board feet. Ten boards total 40 board feet. At $5 per board foot, the estimated cost is $200.
Assumptions & limitations
Assumes identical rectangular boards. Nominal dimensions, surfacing allowances, and hardwood tally conventions can make an invoice differ. Excludes tax, delivery, defects, and cutting waste.
Common questions
Is a board foot the same as a linear foot?
No. A board foot measures volume; a linear foot measures length without accounting for width or thickness.
Should I use nominal or actual dimensions?
Use actual dimensions for physical volume. For a quote, match the dimension convention used by your supplier.
Units reference
The calculation follows the method above. This reference supports the units and conversions.
NIST: units and conversion factors ↗Formula and worked example checked against automated test cases. About our methodology.