How is the billing weight of air freight calculated? Why may the actual weight differ from the billing weight?

2026-01-05 11:24:13

The billing weight in Air freight primarily follows the "larger-of-two-values" principle, which means comparing the actual gross weight and volumetric weight of the cargo, and using the larger value as the basis for billing. The actual gross weight refers to the total weight of the cargo itself plus packaging materials, typically measured in kilograms. The volumetric weight, on the other hand, is calculated using a fixed formula to balance the occupancy of cabin space by lightweight but bulky cargo. A common formula is "volumetric weight (kg) = length (cm) × width (cm) × height (cm) ÷ 6000" (some airlines or routes may use ÷5000, subject to specific quotation terms).

The core reason for the discrepancy between actual weight and billing weight is the difference in cargo density. For heavy cargo with high density (such as metal products, machinery and equipment), its actual gross weight is often greater than its volumetric weight, and it is charged based on the actual gross weight. For lightweight bulky cargo with low density (such as textiles, plastic products, large toys), the volumetric weight can far exceed the actual gross weight, and it is charged based on the volumetric weight. For example, a batch of textiles with an actual gross weight of 20kg and a packaging size of 100cm×80cm×60cm has a volumetric weight of 100×80×60÷6000=80kg, and the final billing weight is calculated as 80kg. In addition, some special cargo (such as dangerous goods, oversized items) may involve special billing standards, which need to be calculated separately in accordance with airline regulations.