If you’ve shipped a package within the last few years that was fairly lightweight but required a large box, you may have found yourself wondering about the cost to ship something that wasn’t all that heavy. Your shipping charges for that package were likely determined according to dimensional weight as opposed to actual gross weight. What is dimensional weight and how does it impact your cost?
What is Dimensional Weight?
Dimensional weight (DIM) may also be referred to as volumetric weight or less commonly, cubic weight. Dimensional weight is an estimated weight determined by multiplying the package dimensions of length x width x height, and then dividing by a dimensional factor (in the U.S., it’s 139). This method of weighing a package is used to help carriers account for the space or volume that package will require for shipping. Using only actual weight (gross weight) gives an incomplete picture of the space requirements the carrier needs to plan for to transport the package. That may sound vague so let’s explore an example:
For this example, imagine you have two completely identical boxes. You fill the first box with self-help books to send to your eccentric 72-year-old aunt. You fill the second box with feathers for your nephew’s handmade owl costume for the school play. When you take them to your shipping provider, the box full of books will weigh far more than the box full of feathers, however, because the boxes are the same size, they require the same amount of space for the carrier to transport. If calculated by gross weight alone, it would appear that the carrier will need far less space to transport the box of feathers than the box of books.
What Dimensional Weight Means for You
In 2007, most commercial shipping companies such as UPS, FedEx and DHL, as well as the U.S. Postal Service all began using DIM when calculating prices to better account for the space that package will take up in a shipment (its volume). In many cases, the company will charge whichever is higher–the DIM or the actual weight. The downside for consumers is that lighter weight items that require a bigger package will cost more to ship than if the pricing were based on gross weight.
One way to avoid overpaying to ship a lightweight item is to consider if another type of packaging would safely substitute for a box. In our example above, shipping the feathers in a large plastic shipping envelope/poly-bag changes the dimensions of the package and takes up less space than the box, which results in a lower cost to ship. You’ll just want to make sure that whichever type of packaging you choose will not risk damaging the item you’re shipping.
DIM makes sense for the carriers who transport packages because it allows them to better account for the space requirements of packages within a larger load or shipment. However, it can result in confusion for consumers if they don’t know much about it, and potentially a higher cost to ship a lightweight package than they expected. Understanding DIM and how it impacts your cost can help you make the most cost-efficient packaging choices. Of course, if you have any questions or need assistance choosing the best packaging option to ship your item, ShipOnSite is here to help!