Calculate board feet from lumber thickness, width, length, and quantity. Enter actual lumber dimensions, including fractional sizes, to estimate total board feet and wood volume.
Calculate Board Feet
How to Calculate Board Feet
Board feet measure the volume of lumber. One board foot equals 144 cubic inches.
For multiple boards, multiply the board feet for one board by the quantity.
Example: 1 × 6 × 8 Lumber
A board measuring 1 inch thick, 6 inches wide, and 8 feet long has a length of 96 inches.
One 1 × 6 × 8 board therefore contains 4 board feet when the nominal dimensions are used.
Board Feet Reference Table
| Lumber Size | Length | Approx. Board Feet |
|---|---|---|
| 1 × 4 | 8 ft | 2.67 |
| 1 × 6 | 8 ft | 4.00 |
| 1 × 8 | 8 ft | 5.33 |
| 2 × 4 | 8 ft | 5.33 |
| 2 × 6 | 8 ft | 8.00 |
| 2 × 8 | 8 ft | 10.67 |
| 2 × 10 | 8 ft | 13.33 |
| 2 × 12 | 8 ft | 16.00 |
Nominal vs. Actual Lumber Dimensions
Lumber sold under a nominal size often has smaller actual dimensions after drying and surfacing. For example, a board sold as 2 × 4 often has actual dimensions close to 1.5 × 3.5 inches.
Use actual dimensions when estimating the physical volume of lumber. This calculator accepts decimal measurements, so dimensions such as 1.5 inches and 3.5 inches work directly.
What Is a Board Foot?
A board foot is a unit of lumber volume. One board foot equals 144 cubic inches, or the volume of a board measuring 1 inch thick, 12 inches wide, and 1 foot long.
Board feet are widely used when estimating quantities and pricing hardwood, rough-sawn lumber, slabs, and other wood products sold by volume.
Board Feet vs. Linear Feet
Linear feet measure length only. Board feet measure volume by considering thickness, width, and length.
Two boards with the same linear length may contain different amounts of wood when their thicknesses or widths differ. Board feet account for all three dimensions.
Frequently Asked Questions
The standard formula is thickness in inches × width in inches × length in inches ÷ 144. Multiply the result by the number of boards for total board footage.
Using nominal dimensions, a 2 × 4 × 8 contains about 5.33 board feet. Actual dimensions produce a different physical volume.
Use actual dimensions when estimating the physical volume of lumber. Nominal dimensions are useful when a lumber price or estimate is specifically quoted using nominal sizes.
One board foot equals 144 cubic inches.
Yes. Enter decimal dimensions such as 1.5 inches, 3.5 inches, or 5.25 inches. This is useful for calculating board feet from actual surfaced lumber dimensions.
No. Linear footage measures length, while board footage measures volume using thickness, width, and length.