Materials Calculators

Board Foot Calculator

A board foot is the volume unit lumberyards price hardwood by — one board foot is a piece 1 inch thick, 12 inches wide, and 12 inches long (144 cubic inches of wood).

Nominal thickness in inches (e.g. a 2×6 is 2).

Length in inches — an 8 ft board is 96 in.

Total board feet

4bd ft

Per piece
4 bd ft

How it’s calculated

Board feet = (thickness × width × length, all in inches) ÷ 144, multiplied by the number of pieces. With every dimension in inches, the 144 converts cubic inches to board feet. If your length is in feet, multiply by 12 first — an 8-foot board is 96 inches.

Worked example

A 2-inch by 6-inch board, 8 feet (96 inches) long: (2 × 6 × 96) ÷ 144 = 1,152 ÷ 144 = 8 board feet. Ten identical boards come to 80 board feet.

FAQs

Should I use nominal or actual board size?
It depends on the lumber. For softwood framing — a “2×6” — use the nominal size; that's how it's sold and tallied even though the dressed board is a bit smaller. Hardwood is different: board feet are figured from the actual rough dimensions, with thickness in quarters (4/4 = 1 in, 8/4 = 2 in) and no nominal “2×6.” When in doubt, use the size your supplier quotes.
What's the difference between a board foot and a linear foot?
A linear foot measures length only. A board foot measures volume — it factors in thickness and width too — so two boards of the same length can have very different board footage.
Does the length go in feet or inches?
This calculator takes all three dimensions in inches. If your length is in feet, multiply by 12 first: an 8-foot board is 96 inches.

Sources

  • Board foot defined as 144 cubic inches of lumber (1 in × 12 in × 12 in) — standard US/Canadian lumber convention.