Board footage is the term used for the volume of a piece of lumber. The length, width and depth of a board is required to calculate board footage.
Measure the dimensions
Measure the length from top to bottom, width across and thickness of the board using a measuring tape. Convert all measurements to inches.
Multiply length, width and depth
Multiply the length, width and depth. For a board that is 72 inches long, 8 inches wide and 2 inches deep, the result is 1,152.
Divide by 144
When using inches in the calculation, divide by 144, according to The Hardwood Store of North Carolina. In the example, 1,152 divided by 144 results in 8 board feet.