Board Feet Calculator
Volume of lumber, the way the mill prices it. One board foot equals 144 cubic inches.
Board feet (bf) is the standard unit hardwood lumber is priced and sold in. One board foot is a piece 1″ thick, 12″ wide, and 12″ long — or any equivalent volume. Get it wrong at the lumberyard and your project budget goes sideways.
Enter your stock dimensions and quantity. Add a price per board foot to estimate the total cost.
Board FeetBF = (T × W × L) / 144
Total Board Feet
4.00bf
The formula
Board feet = (Thickness × Width × Length) / 144, where thickness and width are in inches and length is in inches. If your length is in feet, divide by 12 instead — or just use the unit toggles above and let the calculator handle it.
Quick examples
| Dimensions | Board feet |
|---|---|
| 1″ × 6″ × 8′ | 4.00 bf |
| 1″ × 8″ × 10′ | 6.67 bf |
| 5/4 × 6″ × 8′ | 5.00 bf |
| 2″ × 10″ × 12′ | 20.00 bf |
| 4/4 × 4″ × 6′ | 2.00 bf |
A few gotchas
- Nominal vs. actual. A "1×6" softwood board is actually 3/4″ × 5-1/2″. Hardwood is usually sold rough or surfaced — measure what you're actually buying.
- Quarter system. Hardwood thickness is often quoted in quarters of an inch: 4/4 = 1″, 5/4 = 1-1/4″, 6/4 = 1-1/2″, 8/4 = 2″.
- Round up. Yards typically round to the nearest tenth or quarter of a board foot per piece. Your invoice may not match this calc to the penny.