Box Sizes: How to Measure a Box for Box Dimensions (+Top Box Styles)


These days, you can ship just about anything in a box. 

There’s a box for nearly any size or shape item. 

Need a box for some perishable meat? No problem. A bulky mattress? That can easily be delivered – in a box. A fragile 18th-century chandelier? Too easy. 

Rest assured, if you need to ship it, there’s a box for you.

Let’s dive right into how to measure a box, so you’ll know how to pick the right box size and style for your specific needs.

How to Measure a Box: Finding Your Box Size 

How to Measure a Box Finding Your Box Size

First off, you need to get the box size right.  

You’ve probably heard that old saying, “measure twice and cut once.”  

Well, it’s relevant to box measurements as well. Before you place a large order for custom boxes, you need to make sure you’re ordering the right size for your printing and distribution processes. And simply eye-balling your measurements isn’t going to cut it. 

If you want a jumping-off point measure to help gauge standard box sizes, consider the most common size shipping box is 16”x12”x12”, a 1.5 cubic foot box.

The critical and crucial thing to remember when measuring the dimension of a box is that there are only dimension of two measurements – the interior and exterior measurement. A common 16″x12″x12″ box? Those are the inside box measurements. Outside, that same box measures 16 3/8×12 3/8×12 5/8″.

As you can see, often these box dimensions can be close, but you need to know which is which to avoid costly mistakes. You’d hate to measure a box to have its dimensions be just a ½ inch off and not be able to fit any of your products in the box.

When you see the box measurements listed in a catalog or a website, they’re typically referring to the interior dimensions.  

Box sizes are measured by their internal dimensions, and are are listed in the order of length, width, and height (L x W x H). 

If you’re measuring for a custom box, you should measure the exact cubic size to the closest 1/10th of an inch. That’s pretty precise, so double-check your numbers with a ruler or a tape measure. 

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Now let’s talk about the exterior measurement of the box, which will determine your shipping costs.  

While the costs of shipping vary widely between services and carriers, you can ballpark what you might expect to pay using their specific box size guidelines. FedEx and USPS offer fairly straightforward guides.

Obviously, anything that falls outside of their basic pricing guidelines could be subject to even higher costs.

After you’ve packed up your box and taped it shut, measure the inside dimensions against the exterior, so you’ll know how much volume the box will take up on the truck. The volume of a square box is the cube of length of the side of the square box. Put another way, if you’re shipping in bulk, the exterior measurements will also give you an idea of how many boxes you can fit on a pallet.

When you begin to measure dimensions before printing, note that manufacturers have manufacturing variance. Acceptable manufacturing variance is the difference between estimated and actual costs of a full production run, which typically range above or below 10% of the estimated cost.

Box Styles Explained: How Boxes Are Built

Box Styles Explained How Boxes Are Built

So now, you should have a good grasp size box sizes you need, but now comes the tricky part.  

There are virtually hundreds of box styles to choose from. I know, who would have thought there could be such a variety.

But consider for a minute all of the different products and items and things and knick-knacks that ship on a daily basis. Remember our earlier examples? Perishable meat, bulky mattress, fragile 18th-century chandelier?

You need a lot of different square boxes to ship a lot of different products. And this is the nuts and bolts of packaging.

You might have the prettiest looking box. You might offer the best possible product. But a mismatch between the two can result in damaged goods or a poor unboxing experience for the consumer.

Nobody wants that.

Let’s take a deep dive into all of the possible box types and styles to ensure you have that winning combination that will make both your customers and your brand happy.

Finding the Best Box Type for Your Strength and Build Requirements 

The majority of retail packages that you’ll see lining the shelves of any brick-and-mortar store – from cereals, milk, cosmetics – come in carton boxes. While these are one of the most well-known and diverse box types available, they aren’t intended for shipping.

For our purposes below, we’ll be considering shipping needs as well. And when discussing shipping boxes, the primary package type being referenced is the corrugated box

Most often constructed of three layers – two layers of fiberboard (container or linerboard) surrounding a fluted corrugated medium (a wavy piece of fiberboard) that helps give the box its strength and durability. 

Consider the difference between a cereal box (a single sheet of paperboard) versus a basic moving box (the corrugated box). It’s easy to see why the latter is favored for shipping and fulfillment.

These corrugated boxes can be used for all manner of goods – everything from toys and electronics to foods and appliances. Even hazardous materials ship in the corrugated box if afforded the right exterior thickness and interior packing material.

The advantages of corrugated boxes for shipping include:

  • High durability

  • Lightweight

  • Relatively low shipping costs

  • Reusable

  • Good protection by itself, outstanding when paired with void fill

  • Comes in practically any shapes or sizes of box

Corrugated boxes come in four different builds. They include:

  • Single Face: A single sheet of fiberboard is glued to a single fluted corrugated medium. Most often, this form is utilized as a heavy-duty packing material and not in the construction of an actual box.

  • Single Wall: This form is your basic everyday corrugated box – the two layers of fiberboard glued on either side to the fluted corrugated medium. Single wall corrugated boxes are the standard for the vast majority of shipping needs due to their strength and efficient material and cost optimization.

  • Double Wall: With an additional layer of protection – three sheets of fiberboard alternated with two fluted corrugated mediums – double wall boxes significantly increase a box’s durability and protection. Although it offers increased protection for bulky or heavy items like electronics, it also adds to your shipping costs. 

  • Triple Wall: As you might have guessed, a triple wall corrugated box is some heavy-duty stuff. It adds another layer of fiberboard and a corrugated medium to the build. The strength is on par with wooden crates. Do you need to ship industrial or medical equipment, big appliances, or large panes of glass? This is what you use to do it.

Taking the construction a step further, there are five different fluted corrugated mediums. The flute variances are based on flutes per square foot and thickness. You can combine different flute styles in custom packaging to adjust dimensional weight, the thickness and durability based on actual weight of what you’re shipping.

  • A-Flute: 33 flutes per square foot and 3/16 inch thickness. Ideal for shipping fragile items.

  • B-Flute: 47 flutes per square foot and 1/8 inch thickness. Ideal for items such as canned goods or for use as interior packing dividers.

  • C-Flute: 39 flutes per square foot and 5/32 inch thickness. Ideal for basic shipping needs and is the most common flute size.

  • E-Flute: 90 flutes per square foot and 1/16 inch thickness. Ideal for smaller fragile items and high-quality printing (think cosmetics packaging or for small glass products). 

  • F-Flute: 125 flutes per square foot and 1/32 inch thickness. Ideal for small retail packaging items.

Different Styles of Corrugated Boxes for Shipping

Different Styles of Corrugated Boxes for Shipping

So that’s how boxes are built. What about the box sizes and forms they can take?

As we noted earlier, it can be a taxing affair to count all of the ways you can shape a box. 

Depending on where you look, you can choose from between 1,500 and 2,000 different options. That’s assuming you don’t have any custom packaging needs.

We’ll wait while you quietly utter “wow” to yourself.

In an effort to keep the details uncomplicated, let’s focus our attention on the most common box forms. Trust us, it’s still a lot.

There are actually six basic box styles – Slotted, Telescope, Rigid, Folders, Self-Erecting, and Interior Forms. Here’s a breakdown of some of the most widely used box styles:

Slotted Boxes

Constructed from one single piece of corrugated fiberboard, these boxes are “slotted to allow for easy folding and assembly. This style of box is the most popular and widely used.

  • Regular slotted container (RCS): Regular slotted containers are the most commonly used corrugated shipping box. They have two sets of flaps, each being half the width of the box, which meet in the middle. You’ll need tape to close it.

  • Half slotted container (HSC): Similar to the regular slotted option except that there’s only one set of flaps instead of two.

  • Overlap slotted container (OSC): This box resembles the regular slotted box, but the two sets of flaps are of equal length, that provides an overlapping enclosure (roughly about an inch to an inch and a half more than the regular slotted box) instead of ones that meet in the middle. You’ll commonly see these boxes fastened with staples instead of tape.

  • Full overlap slotted container (FOL): Like the overlap box, all flaps have an equal length but measure the entire width of the box. Not only are these packages more secure, but they stack easier due to a seamless flat bottom when closed. Both the overlap and full overlap are more expensive to procure.

Slotted boxes also feature center slotted varieties with inner flaps with equal sides that meet and other flaps with various degrees of width side overlap. The snap-lock bottom or 1-2-3 bottom offer a quicker set-up than a regular slotted container and can feature a top tuck or regular slotted enclosure.

There’s also a bellow style top that includes a folding top instead of standing side flaps to secure the box’s top portion.

Other Box Styles to Consider

While slotted boxes are the most popular form of box for shipping, the other styles we mentioned garner plenty of use. These include:

  • Telescope Boxes: Telescope boxes include two separate pieces – a top and a bottom – with one fitting over the other. The main styles include a full telescope design style container (FTD) option formed from two slotted pieces that serve as trays that fit inside each other. The box design style container with cover is similar to the above. Only the top portion or cover of the box does not extend all the way down the bottom portion of the container. Imagine a traditional two-piece shoebox. Other variations include the double cover container (DC), interlocking double cover container (IC), and the full telescope half slotted container (FTHS).

  • Rigid Boxes: Rigid boxes, also called bliss boxes, feature two same size end panels and a body that folds around to create two side panels and a seamless bottom. Once the joints of the box are sealed, the box is considered rigid.

  • Folders: Folders are just that, single pieces of corrugated fiberboard that fold to create a seamless bottom with flaps coming together at the top of the box. Two variants include the one-piece folder (OPF) and five-panel folder (FPF). Another type of folder includes trays that fold and join together to create sturdy containers featuring both a cover or an open top. Other folders feature air cells (flaps that fold over to create additional protection), wraparounds that fit directly around a product, or a high wall or display tray.

  • Self-erecting: Self-erecting boxes feature top panels typical of a regular slotted container with a pre-glued auto bottom. There’s also a self-erecting six corner tray that features a telescope top.

  • Interior Forms: Finally, interior forms are corrugated pieces that serve as interior packing forms. Styles include dividers, liners, pads, partitions, or tubes. Interior forms help further strengthen corrugated boxes and protect and cushion fragile products. Although the added materials can increase costs, custom interior forms can also enhance your packaging presentation and provide customers a wow-worthy unboxing experience. 

Phew. Bet you didn’t know there were so many choices for a lowly box. And the list could go on and on. We haven’t even touched on packaging design. But this gives you an idea of some of your options. 

When deciding on which box size is best for your products, the cost of custom boxes is important, but also keep in mind how long it takes to assemble boxes.  

You may pay more upfront for already assembled boxes, but it might be worth it if you don’t have time to devote to folding the boxes together. 


Before moving on to how to choose the right box size, we would be doing you a disservice if we didn’t include a quick note on mailers. 

Yes, boxes are the primary vessel for shipping the vast majority of products to your customers. However, mailers are a good alternative if the product – or your presentation – may not warrant a full-blown box.

Think items that don’t require the protection a box provides (t-shirts) or flat products that would be swallowed up in a box (smartphone cases, screen protectors, or books). 

Solutions such as bags, Tyvek envelopes, and padded mailers are great box alternatives. If you can’t package a number of small products together or have singular items that need little protection, a mailer might be the way to go. In some cases, they can prove considerably cheaper to ship packages, as well.

Consider How Packaging Fill Impacts Box Dimensions

Consider How Packaging Fill Impacts Box Dimensions

Boxes and shipping are more than just, well, boxes and shipping.

Rarely is an item just flung in a box and shipped off. What goes inside your box is also important. And we’re not talking about the products you ship. Not directly anyway.

Void or infill is an integral part of the box-sizing process. Not accounting for how you plan to pad and protect the products you ship can lead to ordering improperly sized boxes, utilizing more materials than is necessary, or increased packaging and shipping costs. Double check your padding with measuring tape or a ruler to avoid having an incorrect size of box.

Haphazardly piecing together your packaging may also result in dissatisfied consumers either from a less than desirable unboxing experience or damaged goods. Having packaging that’s social media shareworthy is one of your strongest marketing tools, don’t risk losing it with damaged products.

Let’s explore a handful of popular options for void fill and how they can impact the box dimensions and style that you choose.

  • Packaging Paper: Arguably, the most widely used void fill material, packaging paper is excellent for filling space and general product protection during shipping. The two main types of paper include Newsprint and Kraft. Considering both are ultimately just a sturdier form of paper, neither option will have a significant impact when accounting for box sizes. You can also use recyclable paper options.

  • Bubble Wrap: A go-to for many brands, bubble wrap is great because, similar to packaging paper, it’s perfect for filling voids and keeping items safe. It does prove burdensome to store (and DIY options require the purchase of a $4,000 air filling machine). It isn’t the most environmentally-friendly choice for packaging. But it won’t alter your box measuring requirements.

  • Corrugated Paper: The environmentally friendly alternative to plastic bubble wrap, corrugated paper is what’s left of the corrugated box making process. That excess makes for superior material both as basic void fill and protection or for a more appealing boxing presentation. Supremely flexible, modest amounts won’t have an impact on your box measurements. However, incorporate it as a stylish display in smaller packaging (it’s excellent for creating a “nest” to cradle items), and you might need to increase your box size.

  • Inflatables: No, we’re not talking balloons here. Instead, inflatables, also called air pillows, offer some of the best shipping cushioning available. The downside, though, is that due to their looseness within a box, it can lead brands into buying one size fits all boxes. Not great if your aim is to closely match your product, boxing and shipping needs. In addition, while they offer a small storage footprint (they come uninflated), they do require a pricey air filling machine.

  • Custom Inserts: Although it might add to your packaging and shipping costs, customized inserts are excellent for protecting and enhancing the unboxing experience. It will take some extra leg work to get your box measurements and style just right. You’ll need to account for the size of the product, how it will fit within the insert, and how the insert will fit within the box. It can be time-consuming and requires some planning, but it’s well worth the effort.

  • Crinkle Paper: Yep, it’s basically shredded paper that’s crinkled up. Although it’s a bit messy, this form of custom packing makes for a fancy presentation, offers adequate protection for small or moderately fragile items, and will work within practically any box dimensions you choose. That said, we’ll reiterate, it can create a mess, so it’s best used in smaller boxes and doses.

  • Packing Peanuts: Speaking of messes, packing peanuts is a stalwart of the shipping business. They will work for any size box, especially large ones with a lot of void to fill, but they’re not at all good for the environment. We suggest you steer clear of these.

  • Biodegradable Starch Peanuts: If, however, you like the idea of peanuts and packing and filling whatever box size you want with them, we suggest you go green. Biodegradable starch peanuts are essentially the same as regular packing peanuts, only eco-friendly. These are awesome and will be appreciated by your customers. Because, seriously, who wants to drive to a UPS store to recycle old styrofoam peanuts?

  • Double Boxing: Similar to custom inserts, double boxing creates a package within a package effect. In theory, this does aid in protecting items within the product box. Still, you will need to account for securing the smaller product box within the larger box for shipping. Unless it’s part of a specific presentation, this approach will increase your costs and double your box measurement and style considerations.

  • Instapak: Instapak is an expanding foam that conforms to the shape of the item you’re shipping and the box it’s shipped in. It offers good protection, especially for heavy or fragile equipment, and is usable in most box sizes. But it’s not eco-friendly and can be expensive.

  • Molded Pulp: Molded pulp, on the other hand, is eco-friendly since its recycled newsprint or cardboard that acts as a superb and attractive buffer for fragile products (think bottled wine). It is a bit more pricy than basic packaging, and it works best customized to fit your outer box.

When planning out your boxing and void fill options, it’s always a good idea to stick to eco-friendly packaging if you can. 

Ecommerce, as convenient as it is, does generate its share of waste. When planning out your ecommerce box needs, stay cognizant of using only what’s necessary to protect your goods and offer the best unboxing experience possible.

Additionally, using boxes and other packaging made of post-consumer waste may cost you a little more money upfront but can enhance your reputation by showing that you care about the environment.  

How to Pick the Right Box Size

How to Pick the Right Box Size

Of course, the number one deciding factor on which box size you need comes down to the products you’re packaging.  

First off, you need a box size that physically fits your items. Know the dimensions of your products. Yes, this involves more measuring (length, width, and height). 

You’ll also have to decide the most efficient way to fit your product in a box.  

If you’re shipping something like a rug, you may decide to roll it up and put it in a long, narrow box. But there’s not a one box fits all – even for similar products.   

Case in point, I ordered a rug that was thin enough to be folded and put in a mailer. It arrived in perfect condition – all the way from Turkey. So play around and find the best box size and style for your unique products. 

You know that you won’t be able to squeeze a football into a flat box. But, also make sure your box isn’t too big. Packing a single mug in an extra-large box makes zero sense. Who wants to pay to ship air? The right box size should provide a snug fit, so your product isn’t rattling around in there. 

When possible, it’s a good idea to combine products as part of your shipping strategy

If you’re shipping multiple products at one time, you can fit them together. Be sure to wrap them individually or use corrugated inserts to protect them from crashing into each other during transit. 

Also, keep in mind that retail boxes usually aren’t strong enough to be shipped by themselves, as most retail packaging uses some variety of carton boxes. so you’ll have to use a close-fitting outer box for shipping – the double boxing method. 

If the product is breakable, you’ll have to take some extra steps to secure it. You can use void fill like air pillows, crinkle paper, or biodegradable peanuts to cushion it.  

Try several drop tests to make sure your products are safe. It’s also a good idea to do a trial run with your packaging to see if it survives any shipping abuse and arrives safely at its destination.  

Many shippers recommend at least two inches of padding around fragile items. Be sure to adhere to any requirements your shipper has. You’d hate for your insurance claim to be denied because your item was improperly packed. 

Measure Away!

No matter what size, or odd-shaped item you need to ship to a customer, you can bet there’s a box that will get it there in one piece and in style.

Same as you would with any other aspect of your business, carefully plan out what your boxing and shipping needs will be before making any material purchases.

Remember, it’s not just a matter of what you ship that determines the box size and style you need. 

It’s also vital to figure out how much protection an item will need, whether you’re trying to impress with the unboxing experience or simply want to stay within a budget. 

So, measure away and find the right boxes for your unique products. 

If you need help measuring your products to find the right box size, the custom packaging specialists at Refine Packaging can help. Request a free consultation to speak with our team of highly-talented graphic artists and engineers, who will guide you through the packaging process step-by-step to take your packaging to the next level. 

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