E-Commerce Shipping

Save Money By Saving Space: How Dimensional Weights Affect Shipping Pricing

Mon 27 Apr 2015
By Shan Lian

There are four main criteria shipping carriers use to calculate shipping rates: package weight, package size, sender address, and recipient address. Let’s talk about those two first criteria, weight & dimensions and demystify the concept of dimensional weight (DIM).

Back in the late fall, shipping carriers changed their rules, modifying their process for calculating shipping rates to use a package’s size rather than its weight. They call this hybrid concept dimensional weight. This new rule applies to most larger sized, lightweight packages containing items like backpacks, bike helmets, and footballs.

Shipping carriers are wise to saving space and cutting costs. Packages are shipped across borders in trucks, trains, and planes. The bigger the package, the more space it takes up and the less room there is for more packages. More bike helmets on a truck means lower volume of flatter packages and less profit for the carrier. Basing your shipping rate on box dimensions via dimensional weight pricing more accurately reflects the carrier’s true cost to deliver these larger packages.

Didn’t adjust your shipping processes as a result? Let’s talk through how you can optimize your package size and take advantage of this update to save money. First, here are the three steps to determine dimensional weight:

Step 1:

USPS DIM = (L x W x H”) / 194

UPS & FedEx DIM = (L x W x H”) / 166

For international DIM, divide by 139.

Step 2: Round your answer up to the next whole number. This is the dimensional weight (lbs).

Step 3: Then, if this DIM is greater than the actual weight of the package, use this weight to determine the shipping price.




Example from ecommerceweekly.com:


*These are USPS standard rates, not Shippo’s discounted USPS rates.


So why does this matter for your business? If you’re shipping larger, lightweight items, your shipping costs went up since dimensional pricing went into effect. If you want to pay less, be conscientious and optimize for box size. If you’re using Shippo’s discounted USPS rates, you’re already saving money, but why not save more by adapting your packaging?


Helpful Tips:

• DIM weight applies only for Priority Mail parcels exceeding 1 cubic foot (12x12x12in) and going to zones 5-9. Calculate zones here.

• All Flat Rate (Priority Mail & Express Mail) boxes are exempt from DIM weight.

• If the DIM weight exceeds 70 lbs, you’ll pay the 70 lb rate.

Take Action: rethink the way you pack your orders. Use tighter-fitting packaging and fewer peanuts! If you’re willing to be even more flexible, try using padded envelopes or poly bags instead of boxes. For even more ideas, check out this article from practicalecommerce.com.

Next post

Apr 28, 2015
(V) Don’t Let Your Customers Wait

Previous posts

Apr 24, 2015
Big Shipping Update: Faster USPS Rates!

Apr 23, 2015
(IV) You Can’t Have Your Cake and Eat It Too

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