Dimensional weight, also called DIM weight, is a pricing technique used for commercial freight transfer, including courier and postal services.
Since space on a delivery truck is limited, dimensional weight takes into account package density to determine shipping rates. Freight carriers calculate shipping charges based on whichever number is greater: the actual weight of the package or its calculated dimensional weight.
Within ShipBob pricing, when the dimensional weight is greater than the actual weight, the dimensional weight is used instead of the package's actual weight.
Dimensional weight for domestic packages is calculated as follows: (L x W x H)/166.
Dimensional weight for international packages is calculated as follows: (L x W x H)/139.
If you have any questions about what your divisor is, please consult your Account Manager or our merchant care team.
Steps to calculate dimensional weight
1. Measure the length, width, and height of a package, using the longest point on each side. These measurements should take into account any bulges or misshapen sides, as irregularities can incur special handling fees if not incorporated into the initial calculations for dimensional weight.
2. When calculating dimensional weight, most shipping carriers request that you round up to the nearest whole number.
3. Next, multiply those dimensions to get the cubic size of the package. For example, if your package is 24 inches by 24 inches by 24 inches, your package size is the product of these three measurements multiplied: 13,824 cubic inches.
4. Finally, the cubic size of the package is divided by a dimensional factor, also called a DIM divisor. DIM divisors are numbers set by the major freight carriers, such as UPS and FedEx. These factors represent cubic inches per pound.