Calculated from the shipment's dimensions, length, depth and height, then divided by 5000 or 6000 depending on the courier and service. Weight isn't a factor here.

Dead weight was traditionally how shipments were charged. The industry then introduced volumetric weight as a more accurate reflection of true shipping cost, since the physical space a parcel takes up on a lorry, van or aircraft matters as much as how heavy it is.

In the UK, dead weight is typically used for domestic parcels, and volumetric weight for international ones. Volumetric weight is almost always the higher figure, and couriers charge whichever is greater.