Volume is the measure of how much space there is within a three-dimensional object. When something has three dimensions, it has length, width, and height or depth. Volume can be used to find out how much a container holds. Imagine a box that is one foot on each side. We say that the box takes up one cubic foot of space. Now imagine filling a closet with these boxes. The number of boxes that will fit in the closet is the volume of the closet. Volume is measured in cubic units. The formula for volume is Volume = length x width x height (V = lwh).