Air freight or cargo is the shipment of goods you want to transport through an air carrier. Air transportation is a perfect choice for express shipments around the globe.
The chargeable weight of the shipment determines the cost of your air freight. You must learn to calculate the chargeable weight to ensure your budget is well-defined.

This article will explain the chargeable weight calculation for air freight in great detail.
What chargeable weight means
The chargeable weight in shipment is also known as the volume weight. It’s the abstract quantity that’s used in calculating the freight rates.
The chargeable weight takes into account the fact that only the actual weight of your shipment is important for its transportation and also the charge space based on the dimensions.
Hence, a large shipment that’s lightweight is more expensive compared to a compact one with the same weight.
Chargeable weight calculation is done based on your volumetric weight or actual weight. The two are compared, and the larger weight figure calculates the freight rate.
Chargeable weight in air freight
The chargeable weight calculation formula for air freight differs from the others, like the courier service. For the volumetric weight to be calculated, the shipment dimensions and a given divisor are needed.
The international air transport association (IATA) recommends the 6000 divisors for air freight.
Why do shippers calculate based on air freight chargeable weight?
Air freight shipments use chargeable weight because large goods with a light overall weight could take up more space on the airplane than a small heavy item.
Hence with chargeable weight, carriers can account for both the weight and size of goods and use the larger value in calculating the final rate.
With this method, the government can balance your payments, and no one client pays more or less than the other.
Traders use the greater of the two figures to ensure the shipping charges you pay are fair. This also provides a fair rate for the shipping of the company.
Each plane has a carrying capacity, which can be met when the weight limit is met, or the space fills. The carrying limit determines the monetary limit of the haul.
Using the chargeable weight calculation ensures the carrier receives a fair price for the weight or space contributions in their carrying capacity.
What’s the gross weight of the cargo?
Gross weight is also known as the total weight of the cargo. This is the weight of the product you’re shipping and the packaging you used to wrap it.
The gross weight is used to ensure the amount of cargo transported is within the legal limits. The variations and limits of the planes vary according to the aircraft, the states, and the regions.
How gross weight is calculated for air freight
Most measurements are in imperial units like pounds; hence after calculating the shipment weight and the pallet, you must convert the sum into kilograms.
Air freight volumetric weight
The volumetric weight of the cargo is also referred to as the dimensional weight. This is the estimated weight value of your goods based on the package width, length, and height.
Volumetric weight is the theoretical weight calculated using a chosen minimum air cubic conversion factor that the freight converter chooses.
The 167 cubic conversion factor is the most used, and when using this air conversion, ensure the volume and weight are in metric.
This means kilograms for weight and cubic meters for volume. This will be used to calculate the actual weight.
Calculating air freight volumetric weight
To calculate the volumetric weight, you should ensure the measurements are converted to meters and cubic meters.
Difference between gross and volumetric weight
You must understand the difference between volumetric weight and gross weight for a seamless air freight shipment.
Volumetric weight is the amount of space your cargo takes on the plane converted to its weight equivalence.
Gross weight is the actual weight in KGs of your cargo, including the pallets and the packaging.
The freight forwarder determines these two weight variables so they can quote your chargeable weight. The chargeable weight is the greater one between the gross and volume weight.
When submitting information on a quote, ensure you provide all the information you can to receive an accurate chargeable weight figure.
Reasons for calculating the air freight chargeable weight of shipments
The reason behind taking the two cargo weight measurements (volume weight and gross weight) to calculate the air freight chargeable weight of your cargo is based on the principle below:
Think about a steel and cotton shipment. The cotton cargo will take up more space than the steel shipment. However, the steel shipment will weigh more. Should both be charges based on the cargo weight or volume?
Therefore, taking the two measurements optimizes the process and ensures there isn’t any bias in the payment of the cargo charges.
How to calculate chargeable weight
The following are the ways you can use to calculate the chargeable weight of your cargo:
Where gross weight is less than volumetric
Sometimes the volumetric weight of your cargo becomes greater than the dimensional weight. In this case, the freight forwarder will choose the volumetric weight to be charged as the chargeable weight.
The following is an example:
- Width (w) = X in
- Length (l) = Y in
- Height (h) = Z in
- Number of boxes =S
- Gross weight (g) = R lb
Step1: Calculate the volume of the cargo
Volumetric weight = (width*length*height)*2
Use the figures above
Step 2: Convert to cubic meters
You can convert the cubic inches to meters using the formula: 61024cubic inches=1cbm
Step 3: Finish the volumetric weight
The air cubic conversion factor = 167
Volume weight = CBM*167
Step 4: Convert the weight to KGs
To convert the pounds to kilograms, use the formula below:
1lb = 0.4536kg
Step 5: Compare the volumetric and gross weight
Here, you need to compare the gross weight and the volumetric weight of the cargo to get the actual weight. This is in steps 3 and 4.
Where gross is greater than volumetric weight
The following is how you calculate the actual weight when the gross weight is greater than the dimensional weight:
- Width (w) = X in
- Length (l) = Y in
- Height (h) = Z in
- Number of boxes =S
- Gross weight (g) = R lb
Step 1: Calculate the air freight shipment volume
Volume = width*length*height
Step2: Convert the inches to cubic meters
Follow the formula below to convert cubic inches into meters: 61,024cubic inches=1cbm
Step 3: Finish calculating the dimensional weight
The air cubic conversion factor = 167
Volumetric weight = CBM*167
Step 4: Convert the weight to KGs
To convert the pounds to KGs, use this formula: 1 lb. = 0.4536kg
Step 5: Compare the gross and dimensional weight
Finally, compare the gross weight in step 3 and the volumetric weight in step4
Calculating the air freight chargeable weight of an irregularly shaped container
When you have an item that’s irregular shapes, here is how to calculate the chargeable weight:
You must follow the same steps as a normal container; however, know the right measurements.
Once you’ve listed the measurements, you can use the above formulas.
Also, you may consider sending us a message to help you get the right measurements. Luckystar is happy to help.