Calculate board feet for timber and lumber — enter the thickness, width, length and number of boards to get total board feet and the volume.
| Item | Value |
|---|
A board foot is the standard unit for measuring hardwood and rough lumber volume. One board foot equals a piece 1 inch thick, 12 inches wide and 1 foot long — that is, 144 cubic inches. It is a measure of volume, not surface area, so thickness matters as much as width and length.
| Board size | Length | Board feet |
|---|---|---|
| 1" × 6" | 8 ft | 4.0 bf |
| 2" × 4" | 8 ft | 5.33 bf |
| 1" × 12" | 10 ft | 10.0 bf |
| 2" × 6" | 12 ft | 12.0 bf |
Suppose you need eight lengths of 1-inch by 6-inch hardwood, each 8 feet long. Board feet per board is (1 × 6 × 8) ÷ 12 = 4 board feet. Multiply by eight boards for 32 board feet total. If the timber is priced at $12 per board foot, that’s 32 × $12 = $384 for the order.
One of the most common timber-buying mistakes is confusing board feet with linear or square feet, and they measure completely different things. A linear foot is just length — a 1×6 board and a 2×12 board are both "one linear foot" per foot of length, even though the second contains four times the timber. A square foot measures surface area and ignores thickness entirely. A board foot, by contrast, measures volume: thickness times width times length. That’s why hardwood and rough-sawn timber are priced per board foot — it’s the only measure that reflects how much actual wood you’re buying. When comparing quotes, always check whether a price is per board foot, per linear foot or per length, because the same number means very different amounts of timber.
Board feet are most commonly encountered when buying hardwoods and specialty timbers, which are sold by volume rather than by the length. Softwood framing timber at a hardware store is usually priced per length or per linear metre, but a timber yard selling oak, blackwood, jarrah or imported hardwoods will quote per board foot. Knowing how to calculate board feet lets you compare prices accurately and check that a quoted amount matches what you actually need for a project — whether that’s a table top, shelving, or decking. When you’re working from a cutting list, calculate the board feet for each different board size separately, then add them together for the total order.
How do I calculate board feet?
Multiply thickness in inches × width in inches × length in feet, then divide by 12. For example, a 1" × 6" board that is 8 ft long is (1 × 6 × 8) ÷ 12 = 4 board feet. Multiply by the number of boards for the total.
What is a board foot?
A board foot is a unit of timber volume equal to a piece 1 inch thick, 12 inches wide and 1 foot long — 144 cubic inches. It is the standard way hardwood and rough-sawn lumber are measured and priced.
Is a board foot the same as a linear foot?
No. A linear foot only measures length, while a board foot measures volume (thickness × width × length). Two boards of the same length can have very different board-foot amounts if their thickness or width differs.
How do I convert board feet to cubic metres?
One board foot is about 0.00236 cubic metres. This calculator shows both, so you can order in board feet and check the metric volume. Enter your board size and quantity above.
What is a board foot?
A board foot is a unit of timber volume equal to a piece 1 inch thick, 12 inches wide and 1 foot long — 144 cubic inches. It’s the standard way hardwood and rough lumber are priced.
How do I calculate board feet?
Multiply thickness (inches) × width (inches) × length (feet), then divide by 12. A 1×6 board 8 ft long is (1 × 6 × 8) ÷ 12 = 4 board feet.
Is a board foot the same as a linear foot?
No. A linear foot only measures length, while a board foot measures volume. Two boards the same length can have very different board-foot amounts if their thickness or width differs.
How do I convert board feet to cubic metres?
One board foot is about 0.00236 cubic metres. The calculator shows both, so you can order in board feet and check the metric volume.
Does board foot apply to dressed timber?
Board feet are traditionally used for rough-sawn hardwood measured at its nominal size. Dressed (planed) timber is slightly smaller, but it’s usually still priced on the nominal board-foot size.