Figure board feet before buying lumber
Board feet is how hardwood is priced. Convert thickness, width, length, and count into the volume unit the lumberyard charges by.
Tools used in this guide
The job
A board foot is 144 cubic inches — a piece 1 inch thick, 12 inches wide, 12 inches long. Hardwood yards quote prices per board foot, so the shopping skill is converting an odd-sized cutting list into that unit.
Enter the pieces
Type nominal or actual thickness and width in inches, length in inches or feet, and the number of identical pieces. Add a price per board foot to see the extended cost.
- Use actual dimensions when the lumber is already planed — a "4/4 rough" board is about 1 inch, but S4S stock is 13/16.
- Length in feet is normal for lumber; inches work for small parts.
Worked example
Five boards at 1 × 6 × 96 inches is 5 × (1 × 6 × 96 ÷ 144) = 20 board feet. At $6.50/bf that is $130 before tax and cutoff waste.
Where it stops
It computes volume only — it does not optimize cutting layouts, convert to linear feet, or account for grading waste. Inputs are capped at 1,000,000 pieces, 10,000 inches for thickness and width, 120,000 for the length field (in the unit chosen), and a unit price up to 1,000,000. Lumberyard minimums and premiums are yours to add.