Volumetric Weight

Volumetric weight converts a package's dimensions into an equivalent weight using a divisor set by the carrier. The shipment is then charged on whichever is greater: its actual weight or its volumetric weight. This is how carriers avoid losing money on a large box of pillows.

The divisor is a commercial variable, not a physical constant. Air freight commonly uses 5,000 for centimetre dimensions; road and courier operators use a range of divisors, and a lower divisor produces a higher chargeable weight. When comparing quotes, comparing divisors matters as much as comparing rates.

For shippers, packaging design is the lever. Reducing a carton's dimensions even slightly can drop it below the threshold where volumetric weight starts to bind, and for high-volume despatch that is often a larger saving than negotiating the rate itself.