How WMS Box Optimization Saves You Money on Shipping

Stop Overpaying for Air: Why Box Optimization Matters

If you’re shipping products in boxes that are too big, you’re not just wasting packaging—you’re wasting money. Major carriers charge based on dimensional weight (DIM), not just actual weight, and if your packaging isn’t optimized, you’re footing the bill for air.

Box optimization in a warehouse management system (WMS) helps businesses pack smarter, reduce costs, and ship more efficiently. Here’s how it works—and how 3PL Center puts it into action.

What Is Box Optimization?

Box optimization is a feature within a WMS that automatically selects the smallest, most efficient packaging for each order. It evaluates the size, shape, and fragility of the items being shipped. Then it matches them to the right box or mailer—minimizing void fill, wasted space, and oversized package fees.

Instead of your team guessing which box to use, the system decides in real time, ensuring every package is right-sized.

The Real Cost of Dimensional Weight

Carriers like UPS, FedEx, and USPS use dimensional weight pricing to calculate shipping costs. That means if your box is too big—even for a lightweight product—you’ll still pay more. Carriers charge based on the box’s volume, not its weight.

Example:
A lightweight desk lamp in a large box could cost $25 to ship instead of $12, simply because of the extra space.

How to Calculate Dimensional Weight

To figure out dimensional weight, use this formula:
(Length × Width × Height) ÷ DIM Factor
For most domestic shipments, carriers use a DIM factor of 139.
Example: A box measuring 20" × 14" × 10" = 2,800 cubic inches.
2,800 ÷ 139 = 20.14 lbs — that’s your billable weight if it's higher than the actual weight.

How a WMS Optimizes Box Selection

Here’s how modern WMS box optimization works behind the scenes:

Automated decision-making
The system chooses the best box for each order, factoring in dimensions, weight, and fragility.


Box library management
Every available packaging type—bubble mailers, poly mailers, custom cartons—is stored and categorized in the system.


pSmart combinations
Orders with multiple items are grouped to minimize packaging waste while protecting products during transit.


Data-driven adjustments
Over time, the WMS learns which box options work best for common SKUs and order combinations.

How 3PL Center Helps You Save with Smarter Packaging

At 3PL Center, box optimization is built into our WMS—and it’s saving our customers thousands.

Here’s what we provide:

Automated box selection for every order
Our system calculates the most efficient box size to reduce DIM weight charges and packaging waste.


Access to a wide variety of materials
We stock everything from poly mailers and bubble mailers to custom boxes—so your products are always packed right.


Higher DIM factor for even greater savings
We ship in high volume with major carriers. That lets us negotiate higher DIM factors than standard—helping you avoid dimensional weight charges in many cases.


Rate shopping included
We don’t just pack better—we also find the best shipping price using our rate shopping feature.


Oversized product expertise
If you ship e-bikes, furniture, or fitness gear, our box optimization works alongside our oversized shipping strategies to minimize costs while keeping products protected.

Final Thought: Smart Packaging = Real Savings

Dimensional weight fees aren’t going away. But with the right WMS and a 3PL that understands optimization, you can minimize those costs.

Ready to stop overpaying for air? Book a call with 3PL Center. See how our box optimization and discounted shipping rates can work for your business. Get a quote today.