Dimensional Weight and Shopify Shipping Explained

Although you may have the same FedEx/UPS account credentials, you may be seeing different prices for the same package in Shopify and Shippo.



The Calculated rate is based on different factors across the two platforms.


Dimensional Weight Explanation 

In January 2015, both FedEx and UPS switched to dimensional weight pricing for all shipments.

Dimensional weight is a calculation of the cubic volume of a package.

Dimensional weight = (height x width x length) / “dimensional factor”

This dimensional factor is set differently by each carrier. For both FedEx and UPS this dimensional factor is 166 for domestic shipments within the US and 139 for international shipments. FedEx/UPS will consider both the actual package weight and the dimensional weight when searching for rates and display pricing for whichever is greater.

In Shippo, you’re required to input both the dimensions and the weight of a package in order to search for shipping rates. This means the rates you see in Shippo are as accurate as possible. In Shopify, live carrier shipping rates are only based on the weight of the item(s) in the order.



If you’ve set your weights in Shopify as the actual item weight, rather than the dimensional weight, FedEx/UPS shipping rates may not be calculated accurately.

If the actual item weight is greater than the dimensional weight, then you will see the same price in Shopify as you will in Shippo. However if the dimensional weight is greater than the actual item weight (as it often is), then the rate you see in Shopify will be underpriced, and the rate displayed in Shippo will be higher.


To learn more about how to set carrier calculated shipping rates in Shopify, you can check out this section of the Shopify Manual.

For a more detailed description of dimensional weight pricing and how this could affect how much you spend on shipping, check out this article from Practical Ecommerce. The article also includes helpful hints on how to lower your dimensional weight shipping costs.  



This does not apply for customers who are connected through the API. This only applies to our customers who are using the Shippo dashboard.


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