Chargeable Weight
Chargeable weight is the figure a carrier actually invoices — the higher of a shipment's actual (gross) weight and its volumetric (dimensional) weight. Light but bulky cargo occupies space the carrier could otherwise sell, so it is charged on volume rather than scale weight.
For air freight, the IATA volumetric divisor is 6,000 (cm³ per kg). Express and courier carriers often use 5,000. For ocean LCL, the equivalent rule is W/M, where 1 CBM is treated as 1,000 kg.
Chargeable weight is why a carton of pillows costs far more to fly than its scale weight suggests. Understanding it lets shippers pack smarter — reducing dimensional weight — and lets forwarders quote accurately instead of being caught out by a volumetric surcharge.
A carton measures 60 × 40 × 50 cm and weighs 8 kg. Volumetric weight = (60 × 40 × 50) ÷ 6000 = 120,000 ÷ 6000 = 20 kg. Since 20 kg > 8 kg actual, the airline charges on 20 kg.
What is the volumetric divisor?
It converts volume to weight. Air freight uses 6,000 (cm³/kg); express couriers often use 5,000. A smaller divisor produces a higher volumetric weight.
Why is my light shipment charged more than it weighs?
Because it is bulky. If its volumetric weight exceeds its actual weight, the carrier bills the volumetric figure — the space it takes up is worth more than its mass.