5 cubic feet dimensions The dimensions of 5 cubic feet depend on the shape of the space or object being measured. For a rectangular box, the calculation is length × width × height. For example, a box that is 1 foot long, 1 foot wide, and 5 feet high would equal 5 cubic feet. If the box is smaller, you would adjust the dimensions accordingly. 5 cubic feet is a common measurement used for shipping, packing, and storage, helping businesses and individuals determine how much space they need for their items.