Last updated: 11/5/2021

When it comes down to it, freight is all about numbersWhat are the dimensions of your shipment? What’s the volume? The weight? How do I calculate cubic feet? How much will fuel cost? How can I determine freight class? Will my pallets fit in a 40′ container? Find the answers to these questions and you’ll know how to estimate your freight costs—and optimize your budgets. 

We worked with our pricing team to put together some quick explanations of the most common freight math you’ll needWe’ll show you how to calculate the cubic feet of your shipmentfigure out if your freight will fit through the opening of a container, and moreWith just a few simple formulas, you’ll be on the road to becoming a freight math expert in no time. 

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Cheat Sheet for Freight Math

Want an easy to use resource for calculating freight costs? Download a printable PDF for your office and workspace.

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Calculating Cubic Feet

(a.k.a. the Volume of Your Shipment) 

In the world of freightbeing able to calculate the cubic feet of your shipment is clutch. Cubic feet are a measure of volume—how much room your shipment takes up. This figure is especially important when it comes to: 

Now that you understand why it’s important, let’s walk through how to calculate your shipment’s volume in cubic feet. 

Calculating Your Fuel Cost

Not knowing the price of fuel up front can lead to some unwelcome surprises when the time for payment rolls around. Be sure to ask your carrier which rate they will use when shipping your goods. With this information and the simple formula below, you’ll know exactly how much you’re expected to pay before you even see your invoice.

Total ocean charges × rate = Fuel cost

In other words, if the current rate of fuel is 24.5%, you will multiply your total freight charges by this percentage. For example, let’s say you are shipping your newest product less-than-container load over the ocean. Your shipment is a total of 450 cubic feet, and your total ocean charges (without fuel) are $1,575. Your calculation will look like this:

$1,575 × .245 = $385.88 in fuel charges

Want to know the total cost, including fuel charges? Here’s a little shortcut: add 1 to the fuel rate percentage before multiplying:

Total ocean charges × (fuel rate + 1) = Total cost
$1,575 × 1.245 = $1,960.88 total cost

Easy, right? We recommend using a calculator (we always do!) so you know your calculations are accurate. You’ll be able to project and forecast your revenue and costs more precisely.



Finding the Density of Your Shipment

(and Why It Matters!)

Once you’ve calculated the volume of your shipment in cubic feet, you’re already halfway to determining the density of your shipment. But before we dive into the math, let’s talk about why density matters. Density is one of the four factors that determines the freight class of your shipment. Freight classification is one of the ways the industry simplifies and standardizes the shipping process. A commodity’s freight class determines its packing requirements, ensuring that everything gets shipped safely. Perhaps most importantly to you, freight class is also used to calculate shipping cost, which is why it’s critical to understand your shipment’s density.

Finally, ocean freight forwarders will look closely at your density to know how your goods will fit into their mix. This is especially true when it comes to LCL shipments, and it can significantly impact your ocean freight pricing.


The 45-Pound Density Rule 

You may be familiar with this obscure rule of ocean freight shipping. It only applies to a handful of shipments, but you should still be familiar with it, in case it ever impacts you. Any extremely heavy/dense shipments may be charged differently. The “45 lb. rule” states that any shipments with a density greater than 45 lbs. per cubic foot will be rated according to this formula: 

Total weight (in pounds) ÷ 45 = Chargeable volume in cubic feet 

Let’s say you had a shipment that exceeds the cargo density limit (45 lbs. per cubic foot). Yours weighs 500 lbs., but it’s only 6 cubic feet. This is how your shipment would be rated: 

500 ÷ 45 = 11 cubic feet 

It’s a fairly simple formula, but it can become confusing when your invoice comes through. Good ocean freight forwarders and logistics partners should communicate this up front—and help you understand it. Don’t be afraid to ask us for assistance.

How to Calculate Cubic Feet Using Other Units of Measurement:

Formulas and Examples

As we mentioned, cubic feet is the standard for the freight industry. But maybe you might have your measurements in other units. How would you convert them into cubic feet? Just use these handy formulas below.

Calculate Feet

This one is just about as simple as it gets. It's almost exactly the same as the formula above for calculating using inches. However, we don't need a conversion factor since everything is already in feet:

Length (in feet) × width (in feet) × height (in feet) = volume in cubic feet 

So if your pallet measures 4′ in length, width, and height:  4 × 4 × 4 = 64 cubic feet 

Calculate Yards

Calculating cubic feet using yards is pretty simple. However, we just need a quick conversion factor to turn yards into feet. Here's the formula:

Length (in yards) × width (in yards) × height (in yards) × 27  = cubic feet 

 If our shipment measures 2 yards by 2 yards by 2 yards, our calculation would look like this: 2 × 2 × 2 × 27 = 216 cubic feet 

Calculate Centimeters

Perhaps you prefer to use the metric system and measure your shipment in centimeters. We've got a formula for that, too:

Length (in cm) × width (in cm) × height (in cm) ÷ 28316.846 = cubic feet 

 So, for example, if your shipment measures 2000 cm in length, width, and height, your calculation would look like this: 2000 × 2000 × 2000 ÷ 28316.846 = 282,517.3 cubic feet 

Calculate Meters

Perhaps you prefer to use the metric system and measure your shipment in meters. We’ve done that math too!

Length (in meters) × width (in meters) × height (in meters) × 35.315 = cubic feet 

If your shipment is 5 meters in length, width and height, your math would look like this: 5 × × × 35.315 = 4,414.4 cubic feet 

Keep these formulas handy, so when you’re requesting a quote or setting up a pick-up or delivery, you can supply your provider with the most accurate information possible.  Now that you understand one of the most important aspects of freight math, let’s cover a few additional freight concepts you need to know. 

Now that you understand why density matters, let’s calculate it!


Start with the Weight of Your Load

Having a scale will help significantly. You can also look at your invoices from previous shipments for an assist. Just make sure you get your weight in pounds. Once you know your weight, you’ll want to run it through this simple formula:

Weight (in pounds) ÷ volume (in cubic feet) = density

So if you have a shipment that is 64 cf and 400 lbs., your equation will look like this:

400 ÷ 64 = 6.25 PCF

As you can see, this shipment is well below the 45-pound limit we mentioned earlier. If you want to discover more about how density translates to freight class, check out our freight class explainer.

Will my pallets fit?

There are a variety of sizes and shapes available for shipping containers. Most Ocean Freight Forwarders and 3PLs like Approved will deal mostly in 40′ and 45‘ standard and high cube containers. The number of pallets and amount of goods will vary with the type of container but here are a few general rules to follow when trying to understand how many of your pallets will fit in a shipping container.

TYPE STANDARD HIGH CUBE 45ft CUBE
External Length 40ft 40ft 45ft
External Width 8ft 8ft 8ft
External Height 8ft 6″ 9ft 6″ 9ft 6″
Internal Length 39ft 4″ 39ft 4″ 44ft 4″
Internal Width 7ft 8″ 7ft 8″ 7ft 8″
Internal Height 7ft 10″ 8ft 10″ 8ft 10″
Door Opening Width 7ft 8” 7ft 8″ 7ft 8″
Door Opening Height 7ft 5” 8ft 5″ 8ft 5″
Internal Cubic Capacity (cu feet) 2,386 2,690 3,040


As you calculate how many of your pallets will fit in a shipping container, consider the following:

As you can see from the chart above, the differences in dimensions for the three most common shipping containers only vary slightly.

However, the extra inches and feet could mean the difference between having to spread your shipment out over multiple containers. In other words, if your goods hang over the edges of your palletsmaking them wider than 4 ft.—you may not be able to place two pallets side by each. That means your shipment will take up more space and, ultimately, cost you more money.

The other thing you’ll want to consider is whether your freight is stackable. This goes back to the structural integrity of your product. If your goods can withstand the pressure of stacking, its footprint will be significantly reduced, allowing your freight forwarder to utilize the space alongside. This will often reduce the cost to you.

Great transportation providers will do everything they can to load safely, securely, while maintaining low costs for shippers. If you aren’t sure how your freight will “stack up,” you can always ask one of our experts for assistance. It’s like a giant puzzle, and we love finding solutions that work for everyone.

All the Formulas to Make Your Freight Math Easy

Now that you understand the formulas behind all of this freight math, you’re on your way to becoming a freightcalculating machine! If you want to get some practice, take some of the data you have from previous shipments and run them through the equations we shared above. If you’ve ever been mystified by the calculations on your freight invoices, this exercise may offer you some new insights. Plus, the next time you need to quote out a shipment, you’ll understand both the “how” behind the calculations and the “why” behind the numbers, so you’ll be well equipped to optimize your freight budget for the future.

Download now

Cheat Sheet for Freight Math

Want an easy to use resource for calculating freight costs? Download a printable PDF for your office and workspace.

Download now

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