LK courier services use volumetric weight or dimensional weight calculating method when pricing items for shipping or transporting. In this way, they measure height, width, and length of a package or goods and calculate the amount based on a set price of kilo grams.
However in the past, freight or courier service in Sri Lanka and abroad measured weight in kilograms. They charged at that time only for the gross weight of a package, item or goods. But they felt later that in this way they incur losses as some goods takes more spaces in vehicles that transport those goods. For example, a lengthy, and wide item will take more space even though that does not weigh that much.
Therefore, courier services worldwide introduced dimensional or volumetric weight calculation methods which take into account the space a package or parcel takes than its heaviness in transportation. Courier services such as Fedex and UPS in 2015 decided to take into account the greater measurement of actual weight of the weight or dimensional of a package. Before their decision, only sizes of some range are taken for pricing through dimensional weight measurement.
Volumetric weight is more a weight measured theoretically rather than actual weight of density of an item. A courier company may decide on the minimum density base upon that the company measures every item to be transported. However, there will be items below this decided minimum density of a courier service. In such cases, a volume of a package will be taken for pricing.
On the other hand, when measuring based on volumetric system, couriers take the lengthiest dimension of a package to calculate the price since there may be different dimensions of a package with many sides. Therefore, an owner of a package may have to pay more than the actual volume of a package under volumetric pricing system. Dimensional weight (DIM weight, cubed weight, volumetric weight) is measured using centimeters or inches.
It may be in3/lb or cm3/kg which means inches per pound and cubic centimeters per kilogram respectively. In other words, it is an inversion of the true density of the package. However, shipping factors may be different with freight operators. Some common shipping factors they use include Imperial Shipping Factor like 166 in3/lb = 10.4 lb/ft3 194 in3/lb = 8.9 lb/ft3, 250 in3/lb = 6.9 lb/ft3 and Metric Shipping Factor like 5000 cm3/kg = 200 kg/m3 7000 cm3/kg = 142.857 kg/m3.
From a customer who wants to ship light objects may feel that the Dimensional Weights measurement system does not favour him. On the other hand, those who want to ship dense objects favour this system. However, they must understand even though a package is light, if it takes a lot of spaces, the courier service that accept it has to charge it based on the space it takes rather than on its actual weight.
All commercial airlines use dimensional weight calculation method. So are freight forwarders and truck carriers. Now ground courier services also charge as per the weight taken via the dimensional measurement system. They employ automated volumetric system in this regard.