Volumetric weight—also known as dimensional weight—is a pricing technique used by shipping companies to ensure that they don’t lose money on large, lightweight shipments (like your pillows). While physical weight is the weight of the shipment according to the scale, volumetric weight is calculated based on the package’s length, width, and height. As a result, that oversized boxful of pillows might be considered heavier than a tiny little box of smartphones.
