Board Foot Calculator
Board feet in rough lumber.
| Board feet per piece | 4.00 bd ft(thickness × width × length ÷ 12) |
| Total for 5 pieces | 20.00 bd ft |
| Dimensions | 1.00 in × 6.00 in × 8 ft |
| Total cost | $120(at the price you entered) |
| Linear feet | 40 lin ft |
Results update instantly and are computed entirely in your browser. For general information and planning only — not engineering, structural or code advice.
About the board foot calculator
Hardwood is sold by volume, not by length, because a board's price depends on how much timber it contains and that is a product of thickness, width and length together. The unit is the board foot: one square foot of lumber an inch thick, which is twelve inches by twelve inches by twelve inches. Thickness, width and length in inches and feet, multiplied together and divided by twelve, gives the board feet in a single piece. The formula is worth memorising because it lets you compare offers. A wide board costs more than a narrow one of the same length, even though both might be sold from the same stack, and a thicker board costs more again in proportion. When a supplier quotes a price per board foot, the total for your project is simply the total board feet multiplied by that rate, plus waste for the cuts your design requires. Rough lumber and surfaced lumber are not the same purchase. Rough stock is sold at nominal dimensions and often measures slightly over, while surfaced boards are planed down and measure slightly under — a nominal one-by-six may finish at three-quarters by five and a half inches. Pricing is normally based on the nominal size, so the board feet you pay for can exceed the usable volume, and it pays to know which convention your supplier uses. This calculator converts your pieces into board feet and total cost. It assumes all pieces are the same size, so run it once per size and add the results for a mixed order. Add a margin for waste and defects, since knots, checks and waney edges are common in hardwood and the usable yield is always less than the nominal volume.
This calculator returns estimates for planning and general information only. It is not engineering, architectural, structural, electrical or code advice, and it cannot replace a qualified professional who has seen the site. Material quantities depend on the actual dimensions, the product you buy and local building codes, so confirm the figures before ordering materials or starting work, and always follow local regulations.