Board Foot Calculator

Calculate the board footage of lumber and estimate your total material cost.

Lumber Dimensions

Thickness (inches)

Width (inches)

Length (feet)

Number of Boards

Common rough lumber thickness:

Price Per Board Foot (optional)

Results

Board Feet Per Board —

Total Board Feet —

Estimated Cost —

How to Calculate Board Feet

For sheet goods rather than solid lumber, plan plywood cuts and sheet purchases; board feet and sheet counts measure different purchases. For a framed wall, estimate wall studs and plates before pricing the lumber; board-foot volume alone does not determine the required member sizes or spacing.

A board foot is a volume measurement commonly used when buying hardwood lumber. One board foot is equal to a board 1 inch thick, 12 inches wide, and 12 inches long.

Board Feet = Thickness (in) × Width (in) × Length (ft) ÷ 12

Multiply the result by the number of boards to find the total board footage for your project.

What Do 4/4, 5/4, 6/4 and 8/4 Mean?

Rough hardwood thickness is often described in quarters. For board-foot calculations, 4/4 represents 1 inch, 5/4 represents 1.25 inches, 6/4 represents 1.5 inches, and 8/4 represents 2 inches.