There are hundreds of box sizes available from FedEx, UPS, and USPS, making it hard for any eCommerce business to figure out how to ship products to customers. Sometimes, it’s even hard just to figure out what your options are, let alone how to choose them and compare final pricing. To help you sort through box sizes, we’ve pulled the latest details from the carriers for 2021 and put them in the tables below.

If you’re unsure of how to start with these, speak to a Red Stag 蜂鸟电竞数据 expert. Our motto of Elevating Expectations by Pursuing Perfection means that we can point you in the right direction of boxes and tools to get started or walk you through how our services can optimize box size selection and product protection for you.

flat rate shipping

FedEx box sizes

FedEx has a broad range of box sizes available for your shipping needs. Regular customers and new businesses can order boxes online or pick them up in a store for a small fee. Once you create a FedEx account, you’ll get access to many free options as well.  We’ve included pricing for boxes to give you as much information as possible, but don’t forget to sign in to your account and review your order options to ensure that you get the right boxes at the best price.

Now, here are three categories of FedEx packaging. They also offer some freight boxes, including flat-rate freight, but you should speak with a fulfillment expert for help determining what’s suitable for your products and how to manage your inventory for these types of shipments.

FedEx standard box sizes

There are many common box sizes you’ll use for your eCommerce operations. Consider the size of your goods and the amount of infill you’ll need to protect your products adequately.

FedEx standard box sizes

Here’s an extensive guide on infill updated for 2021.

Specialty box sizes

Both FedEx and FedEx Office provide multiple specialty boxes in different sizes:

FedEx specialty box sizes

FedEx flat-rate shipping boxes

FedEx flat-rate box sizes

UPS box sizes

UPS freight box sizes

UPS, like most carriers, offers a variety of pre-made packages and boxes for you to utilize. These can sometimes make it easier for you to plan your shipping and fulfillment costs . Choosing a box from a carrier also helps you protect products if you’re new to shipping them. Consider trying out various UPS boxes to see what best fits and protects your products while controlling price. UPS also offers packing and freight shipping services for a wide range of products. These boxes aren’t always standard, so you’ll want to reach out to UPS or contact a 3PL service provider for a reasonable quote and box information.

UPS box sizes

These boxes are available for ordering on UPS. One benefit of making a company account with UPS is that you can order them for free on the UPS website . Note that you’ll end up paying for most boxes at a UPS Store because they market these goods as moving boxes and supplies.

UPS box sizes

UPS also offers packing and freight shipping services for a wide range of products. These boxes aren’t always standard, so you’ll want to reach out to UPS or contact a 3PL service provider for a reasonable quote and box information.

UPS flat-rate shipping options

UPS flat-rate box sizes


UPS offers five flat-rate options, as seen above, and these can generally be applied to the boxes you can get directly from UPS. What’s important to note about these is that you’ll be paying the simple retail rate unless you’ve negotiated a better deal. However, those prices increase if your box weighs more than 50 pounds.

The core difference for UPS flat-rate shipping is that it can be applied to your existing packaging instead of being limited to UPS-branded items. That makes it different than FedEx and USPS.

USPS box sizes

USPS boxes


USPS offers a wide range of box sizes. We’re focusing on their core offering and flat-rate solutions because these tend to be helpful for eCommerce companies. However, they might have other packages that are a better fit for your operations, such as these priority mail DVD boxes .

Use the Postal Service’s store to review its shipping supplies . There are more than 100 options for you, including 72 products that you can get sent to your business for free. For businesses that commonly ship to local areas, you may also want to consider their priority mail regional rate boxes . These options start at a little more than $5 and can hold up to 25 lbs. before other rates will apply.

USPS flat-rate shipping options

USPS flat-rate box sizes

ECommerce understanding: Box size and shipping costs

Your business wants to look at all its options with boxes and try to slim things down because carriers use multiple calculations to set the price for shipping your products to customers. To test and understand these pricing differences, you’ll want to have the existing rate table and a dimensional weight (DIM) scale available .

UPS, FedEx, and USPS use your package’s actual weight and its DIM weight to determine the weight-calculation they apply to your cost. DIM weight is a calculation based on overall box size to build pricing around the volume of your package. This is designed to help the carrier generate revenue based on large but light products. You’ll fill up their trucks quickly with large items, so they’re charging based on that space utilization.

Try our DIM weight calculator here to test pricing from all 3 carriers

Your  eCommerce fulfillment  company can help you find creative ways to stay on top of the DIM weight. This reduction might be shifting your packaging options around to one of the options above or choosing your package designed to slim down overall size while ensuring products are safe.

5 ways RSF works to keep your costs down

eCommerce packaging

  1. Negotiate better DIM rates: By shipping high volumes of large, heavy products with carriers, Red Stag has negotiated more favorable rates . We pass those discounts directly on to you, including higher DIM factors that reduce dimensional shipping costs.
  2. Compare every option: Red Stag 蜂鸟电竞数据 reviews your products during onboarding and every order during the packing phase to find the best possible shipping for that order. We start with cost-effective solutions and DIM weight comparisons to trim down costs while also ensuring your order arrives on time and complete every time.
  3. Optimize boxes for each order: By working together, we’ll determine the correct box sizes for your products and orders, plus the correct infill to protect products while controlling for weight .
  4. Consolidate packaging: When customers order more from you, they still tend to want as many items as possible in as few boxes as possible. We help you make their dream come true by identifying cost-effective ways to consolidate orders. We make it easier to minimize the price for even larger boxes and orders with our special savings on large, bulky goods.
  5. Split orders across boxes: Sometimes, your lightweight goods have significant DIM weight costs because of their size. We work with companies to determine if they can split orders, or even products, across multiple boxes to reduce box size. When there’s a significant reduction, you can often save money by shipping across multiple boxes instead of one oversized, lightweight box.

What’s next for your eCommerce business?

Now that you’ve learned more about box sizes for UPS, FedEx, and USPS, it’s time to start optimizing your packaging and infill for your orders. That’ll ensure you’re spending wisely while keeping customers satisfied. These guides and blogs can help you get started on that journey.

Not sure how to save? Ask a Red Stag expert.