Board Foot Calculator

Calculate board feet of lumber from thickness, width, and length. Add multiple boards and estimate total cost per board foot.

inches
inches
feet
boards
$
Results
—board feet
BF per Board—
Quantity—
Cubic Inches—
Total Cost—
Formula Used
BF = (T × W × L) ÷ 12

What Is a Board Foot?

A board foot (BF) is a standard unit of volume for lumber equal to a piece of wood 12 inches long, 12 inches wide, and 1 inch thick — or 144 cubic inches. Board feet are the standard unit for buying and selling hardwood lumber in North America.

Board Foot Formula

Board Foot Calculation
Board Feet = (Thickness″ × Width″ × Length′) ÷ 12

Where thickness and width are in inches, and length is in feet. For multiple boards, multiply by quantity.

Common Lumber Sizes in Board Feet

Lumber SizeLength (ft)Board Feet
1 × 482.67 BF
1 × 684.00 BF
1 × 885.33 BF
1 × 1288.00 BF
2 × 485.33 BF
2 × 688.00 BF
2 × 8810.67 BF
2 × 10813.33 BF
2 × 12816.00 BF
4 × 4810.67 BF

Lumber Price by Species (per Board Foot)

SpeciesTypePrice Range ($/BF)
PineSoftwood$2 - $5
PoplarHardwood$3 - $6
Red OakHardwood$4 - $8
Hard MapleHardwood$5 - $10
CherryHardwood$6 - $12
WalnutHardwood$8 - $15
White OakHardwood$6 - $12
TeakExotic$18 - $30
MahoganyExotic$12 - $25

Pro Tip: Hardwood is sold by the board foot using nominal (rough-sawn) dimensions. Dimensional softwood (2×4, 2×6) at big-box stores is sold by the linear foot. When buying from a lumber yard, always ask if pricing is per board foot or per linear foot.

Board Foot FAQ

A board foot = 144 cubic inches = a piece 12" × 12" × 1". It's the standard unit for buying hardwood lumber.
BF = (Thickness" × Width" × Length') ÷ 12. A 2×6×8' = (2×6×8)÷12 = 8 board feet.
Pine: $2-5/BF. Oak: $4-10/BF. Walnut: $8-15/BF. Exotic woods: $15-30+/BF.
Nominal = rough-sawn size (2×4). Actual = after planing (1.5×3.5"). Board foot calcs for hardwood use nominal dimensions.