The cost of a shipment can be affected by the amount of space that it occupies on an aircraft, rather than the actual weight. The cost of a shipment can be affected by the amount of space that it occupies on an aircraft, rather than the actual weight.
How is volumetric weight calculated?
To calculate volumetric weight, measure the length, width, and height of the box. Then multiply the results to obtain the cubic size of your package.
Here is an example: Let’s say you have a box measuring 12 inches x 12 inches x 12 inches. Multiplying the three dimensions — 12 X 12 X 12 — gets you 1,278 cubic inches.
For FedEx, UPS, DHL and Aramex dimensional weight divisor is 139, so your package's volumetric weight is 13 lbs. Shipping companies will use the highest of actual or volumetric package weight when calculating shipping cost.