Whether you opt for air freight or sea freight shipping to fulfill your eCommerce orders, the shipment's weight and volume lie at the core of freight rate estimates. Shipments come in varying weight and dimensions; some items like cotton are lightweight but occupy a large volume, and other items may be heavy but do not take up a lot of space. Shipping 1kg of cotton surely makes a difference to shipping 1kg of steel in terms of air freight volume it takes – and this is why freight companies adopt different metrics to calculate the corresponding shipping fees.

Generally speaking, a shipping cost is calculated based on the actual weight or volumetric weight – whichever is of greater value.

Here is a glossary of common terms that you may have come across before discussing cost calculation in further depth.

• Actual Weight (or Gross Weight or Total Weight)

Actual weight is the weight obtained from weighing, as in how heavy your shipment is – including all packaging materials, cushioning materials, pallets, and the weight of the content.

• Volumetric Weight (or Dimensional Weight)

Volumetric weight is the weight regarding the volume of the shipment content by turning the volume into 'weight equivalent' – often shown in the order and format of length (L) x width (W) x height (H).

The calculation of volumetric weight can vary among transportation modes and pricing structures of each volumetric kilogram (kg) or pound (lb).

• Chargeable Weight

Commonly used by air freight companies in calculating shipping fees, chargeable weight refers to either the actual weight or the volumetric weight - whichever is larger will be used. Upon comparison between the actual and volumetric weight, the chargeable weight accounts for the actual shipping fees you have to pay for the shipment.

How is volumetric weight calculated?

While actual weight is obtained by weighing – pretty straightforward, volumetric weight is normally calculated by obtaining the cubic centimeters or inches, then dividing the result by 6000*.

*Remarks: A dimensional divisor (DIM divisor) is the cubic size of a package divided by a dimensional factor. Commonly set to be 5000 or 6000, DIM divisors are subject to change depending on the freight companies, resulting in the varied formula of which the volumetric weight is calculated.

The internationally recognized algorithm is listed as follows:

Length ( cm / inch ) x Width ( cm / inch ) x Height ( cm / inch ) ÷ 6000*

In the following, we will use examples to explain how your shipping cost is calculated under different scenarios.

Scenario 1: Actual weight as Chargeable weight

You want to ship some goods from Paris to Beijing. The shipment comprises 4 boxes - each weighs 25 kgs with a measurement of 60 x 30 x 40 cm.

Actual weight = 4 boxes x 25 kgs = 100 kgs Volumetric weight in kgs using centimeters = ( 60 x 30 x 40 cm ) x 4 boxes / 6000* = 48 kgs The shipment has an actual and volumetric weight of 100 kgs and 48 kgs, respectively.

Conclusion: The actual weight of 100 kgs will be the chargeable weight of this shipment.

Scenario 2: Volumetric weight as Chargeable weight

You plan to ship some commodities from Shanghai to London. The shipment consists of 7 boxes – each weighs 15 kgs with a measurement of 50 x 50 x 80 cm.

Actual weight = 7 boxes x 15 kgs = 105 kgs Volumetric weight in kgs using centimeters = ( 50 x 60 x 70 cm ) x 7 boxes / 6000* = 245 kgs The shipment has an actual and volumetric weight of 105 kgs and 245 kgs, respectively.

Conclusion: The volumetric weight of 245 kgs will be the chargeable weight of this shipment.

Side note: What if the shipment has an irregular shape?

Don't panic – the measurement of its volume is not as complicated as it looks. Measure the longest edge that extends horizontally for the length – the same applies to the width. For the height, measure how long it is from the highest point to the base that extends vertically.

The volumetric weight of irregularly shaped shipments is calculated as follows:

The longest edge ( cm / inch ) x The widest edge ( cm / inch ) x The highest edge ( cm / inch ) ÷ 6000*

Understanding the breakdown of shipment charges is key to the budgeting of your eCommerce business.

For an exact quote for your shipment and order fulfillment, or if you have other inquiries, please drop us a line, and our team will get back to you soon!

Meanwhile, do have a read of the top FAQs we answered about taxes and duties that simultaneously add up your eCommerce shipping fees: https://bonuship.com/en/blog/crowdfunding-fulfillment/top-faqs-answered-about-shipping-duties-taxes-ecommerce