Did you know it costs more to ship 100 pounds of feathers, than 100 pounds of bricks? Shipping costs are determined by volumetric weight, a pricing technique for commercial freight transportation which uses an estimated weight that is calculated from the length, width, height of a package. A less dense item generally occupies more volume of space, in comparison to its actual weight – so when you are transporting items you are essentially paying for the space your product is occupying in the airplane or truck carrying it.