Board feet calculator
Work out board feet and the cost of lumber for any number of boards.
How it works
A board foot is 144 cubic inches: 1 inch × 12 inches × 12 inches. Board feet = thickness (in) × width (in) × length (ft) × 12 ÷ 144. Hardwood is usually priced by the board foot using the rough, nominal thickness, so 4/4 stock counts as 1 inch.
Quick reference
| 4/4 × 6 in × 8 ft | 4.0 bf |
| 4/4 × 8 in × 10 ft | 6.7 bf |
| 8/4 × 6 in × 8 ft | 8.0 bf |
| 5/4 × 4 in × 6 ft | 2.5 bf |
Add 10–20% for waste, defects and offcuts.
Questions
Board feet or linear feet?
Linear feet measure length only. Board feet measure volume, which is how most hardwood is sold.
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