Volumetric weight, also known as Dimensional weight, is used by postal companies and other freight industries and courier services around the world to invoice for the actual space that a parcel, package or pallet takes up in a vehicle or storage area. A vehicle can quickly become full of bulky, lightweight articles long before it reaches its capacity in weight which makes for inefficient use of space.
The basic procedure for calculating volumetric weight is :
The result of this calculation is that if a consignment's density is one-sixth that of water or more, then its volumetric weight is less than the normal weight in kilograms, whereas if its density is less than one-sixth that of water, then its volumetric weight is more than its weight in kilograms. Transport and postal companies will charge based on the greater of these two calculations.
Increasingly, carriers, postal companies and warehouses are using dimensioners to calculate the volumetric weight of their parcels and pallets. Companies with large shipping departments use these systems to measure all outgoing items to ensure that they don't receive back charges from their carrier who invoices using the dimensional weight rate system.[1]
Note that the formula for pallets is different—for pallets, the calculation is to divide by 3,000, not 6,000, so the volumetric weight is twice as much.
International express shipping companies such as DHL apply this formula but dividing by 5,000 instead of 6,000. Other shipping companies may use a different divisor.