Dimensional weight

Dimensional weight, also known as volumetric weight, is a pricing technique for commercial freight transport (including courier and postal services), which uses an estimated weight that is calculated from the length, width and height of a package.

Shipping costs have historically been calculated on the basis of gross weight in kilograms or pounds. By charging only by weight, lightweight, low density packages become unprofitable for freight carriers due to the amount of space they take up in the truck/aircraft/ship in proportion to their actual weight. The concept of dimensional weight has been adopted by the transportation industry worldwide as a uniform means of establishing a minimum charge for the cubic space a package occupies. In fact, UPS and FedEx both announced that starting 2015, shipping charges on all shipments (air and ground) will be determined by greater of the actual weight and dimensional weight of a package. Prior to this announcement, dimensional weight charges were only applicable to packages of a specific size range.

Dimensional weight is a calculation of a theoretical weight of a package. This theoretical weight is the weight of the package at a minimum density chosen by the freight carrier. If the package is below this minimum density, then the actual weight is irrelevant as the freight carrier will charge for the volume of the package as if it were of the chosen density (what the package would weigh at the minimum density). Furthermore, the volume used to calculate the dimensional weight may not be absolutely representative of the true volume of the package. The freight carrier will measure the longest dimension in each of the three axis (X, Y, Z) and use these measurements to determine the package volume. If the package is a right-angled rectangular box (cuboid), then this will be equal to the true volume of the package. However, if the package is of any other shape, then the calculation of volume will be more than the true volume of the package.

Dimensional weight is also known as DIM weight, volumetric weight, or cubed weight. Freight carriers utilize the greater of the actual weight or dimensional weight to calculate shipping charges. Dimensional weight is calculated as (length × width × height) / (dimensional factor). Measurements can be made all in inches or all in centimeters, but the appropriate shipping factor must also be used.

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