The basic board foot calculation uses three measurements: length, width, and thickness. A Board Foot Calculator makes this process easier because you do not have to perform the formula manually for every board. The standard formula uses length in feet and width and thickness in inches, with the result divided by 12. If you have multiple identical boards, the individual result can be multiplied by the quantity. An online calculator handles these calculations quickly, which is particularly convenient when preparing a detailed lumber list for a larger project.