Board Foot Calculator
Calculate the total board feet of lumber for a project. Enter the thickness, width, length, and number of boards to get the total board footage — the standard volume unit used to price hardwood.
Formula
Board Feet = (Thickness[in] × Width[in] × Length[ft] ÷ 12) × Quantity
- One board foot equals a volume of 144 cubic inches — a piece 1 inch thick, 12 inches wide, and 1 foot long.
- Board feet per board = thickness (in) × width (in) × length (ft) ÷ 12.
- Multiply by the number of boards for the total board footage.
- Use nominal (rough) thickness and width for lumber, since hardwood is usually priced on rough dimensions.
- Add a 10–15% buffer for waste, cutting losses, and defects when ordering.
15 boards, 2 in × 8 in × 10 ft
Inputs
- Thickness (in): 2
- Width (in): 8
- Length (ft): 10
- Number of Boards: 15
Each board = 2×8×10 ÷ 12 = 13.33 board feet. For 15 boards that is 200 board feet total.
Frequently asked questions
What is a board foot?
It is a unit of lumber volume equal to 144 cubic inches — a board 1 inch thick, 12 inches wide, and 1 foot long.
How do I calculate board feet?
Multiply thickness (in) × width (in) × length (ft), then divide by 12. Multiply by the number of boards for the total.
Should I use nominal or actual dimensions?
Lumber is usually sold and priced by nominal (rough) dimensions, so use those for ordering and cost estimates.
How much extra should I order?
Add roughly 10–15% for waste, defects, and cutting losses so you do not run short mid-project.
Is a board foot the same as a linear foot?
No. A linear foot measures length only; a board foot measures volume, accounting for thickness and width as well.