Does Size Really Matter? Dimensional Weight & How it Effects Shipping Rates

One major factor in the pricing of shipments is dimensional weight. Whether you ship orders yourself or work with a 3PL, you will likely encounter this. Read to learn more about dimensional weight and how it affects your shipping rates.


What is dimensional weight?

Dimensional weight is the amount of space a package takes up in relation to its actual weight. Dimensional weight is based on the dimensions of the package (length, width, height) instead of the actual weight. Depending on the carrier, you are charged either on the dimensional weight of the package or the actual weight of the package—whichever is higher.

When calculating the weight of an e-commerce order, the actual size of the package should be taken into consideration. Larger packages inherently take up more space, even if some weigh significantly less than others. Dimensional weight aims to correct the previous lack of consideration for how much space a package will take up and how that will affect the cost of shipping it out.


Why is Dimensional Weight Important?

  • Major shipping companies (Ex. UPS, FedEx, USPS, Canada Post, DHL) use dimensional weight to calculate shipping prices.

  • Packages priced according to dimensional weight may reduce shipping costs for brands who pack more efficiently and have a leaner unboxing experience.

  • Reduced packaging can make shipments more environmentally friendly by helping lower fuel emissions and can also help you avoid wasted material.


How Does Dimensional Weight Affect The Cost of Shipping?

Very large and very heavy parcels cost more to ship than very small and light ones. So global carriers use dimensional weight (DIM weight) to balance their shipping costs.

Imagine how often people ship using packaging that’s too big. To keep the products safe, these oversized boxes are packed with extra cushioning. These over-packed boxes fill shipping trucks with cubic feet of unneeded corrugated cardboard, air pillows, thank-you cards, plastic and packing peanuts. In many cases, e-commerce brands are literally paying to ship air.

So, will dimensional weight really change the cost of shipping all that much? If the dimensional weight is the greater of the two values (dimensional vs. actual), it will be used in place of the actual weight to calculate how much it will cost to ship out your order. Because of this, it is best to keep unnecessary packaging to a minimum. If it doesn’t elevate your brand story, take it out. By reducing the amount of packaging, your shipment will take up less space, which could reduce your shipping cost drastically. Dimensional weight pricing can be a great reward to brands who eliminate extra packaging, add-ons and embellishments.


Package dimensions are defined by the length, width, and height of the parcel. These determine how much space the package takes up in the truck or airplane. The smaller each package, the more shipments can fit into the same space. Likewise, larger packages reduce the number of shipments that each vehicle can transport. Package weight directly affects how much fuel it takes to transport the package. Heavier packages cost carriers more in fuel than lighter ones.


3 Types of Weights Shipping Carriers Use

To better understand dimensional weight, it helps to distinguish the 3 types of weights that most carriers use:


Actual weight is measured with a standard scale. U.S. carriers tend to measure actual weight in pounds (lbs) and ounces (oz), whereas Canadian carriers tend to measure weight in kilograms (kg).DIM weight is calculated using the volume of the package – length x width x height. The volume is then converted to a dimensional weight using a carrier-specific divisor.Billable weight is the larger of the actual and dimensional weight. It is used with the carrier’s rate table to find postage costs.


For example:

Package #1 (14”x14”x10”)

Actual Weight = 8 lbs / DIM Weight = 12 lbs / Billable Weight (Shipping Cost) = 12 lbs

Dimensional weight incentivizes everyone to optimize their brands packaging.


Best Practices To Reduce The Effects of Dimensional Weight

Use properly sized boxes. You should aim to use the smallest box (with the smallest volume) possible. Even reducing the size by fractions of an inch can save you on shipping.Always input exact package dimensions. If you forget to do so, you may be paying too much for shipping and be surprised by extra charges from your carrier.Eliminate extra packaging. If you forget to do so, you may be paying too much for shipping and be surprised by extra charges from your carrier.


More Tips & Tricks:

  • Choose packaging to match the size and fragility of your item

  • Explore eco-friendly options like padded or kraft mailers

  • If you are shipping very light products, consider making it attractive for customers to purchase a heavier item in the same order, as that heavier item might effectively ship for free

  • Use OrderGrid as your 3PL partner! A team member will expertly source and select the right packaging for your products. They will help you determine how much cushioning is needed for fragile items, so you’re not overpacking and wasting material, and you’re not under packing and risking damage

Request a consultation with an OrderGrid packaging expert today! Our experts will offer you options that can:

  • Improve packaging efficiency, which may mean less waste

  • Reduce shipping costs

Being more efficient with your packaging is not only a matter of saving money but saving our planet!