If you’re planning on shipping an FCL (Full Container Load) shipment, then weight won’t usually be a factor to consider when working out your costings. As long as your cargo is within the legal weight limits, then the cost of an FCL shipment will depend on the method of shipping and the journey your cargo is making.

With smaller shipments, however, weight can become an important consideration in your cost calculations. We’ll take a look at the varying rules for different methods of shipping, but first, you need to understand the difference between actual weight and volumetric weight.

- Actual weight – how heavy the cargo is, usually measured in kilograms (kgs)
- Volumetric weight – the space that the cargo takes up, usually measured in cubic metres (CBM)

## Ocean Freight

If you’re sending an LCL (Less than Container Load) shipment by sea, your freight forwarder or shipping agent will calculate the weight of the cargo (the ‘weight’) and the cubic volume of the cargo (the ‘measure’). These will be compared on the basis that 1CBM = 1000kgs and the greater of the two will be multiplied by the shipper’s rate per kg.

For example:

- You’re sending cargo that weighs 200kg.
- The cubic volume (length x breadth x width) of the cargo is 1.44cbm.
- To make the two measurements comparable, the weight needs to be converted to become a decimal of 1000kg.
- This conversion makes the weight of the shipment 0.200kgs.
- 44 is greater than 0.200; therefore the cubic volume is the figure used to calculate the freight charge.
- Where the freight charge is £50 x the w/m (weight or measure) the costing for this cargo would be 1.44 x 50 = £72

How your cargo is costed is useful to know as it can affect the way that you pack it for shipping. For example, if your cargo is being costed by weight and not volumetric weight, you could choose to pack your cargo in a way that takes up more space to better protect it during transit. As long as the weight of the cargo stays the same (and remains higher than the volumetric weight), then the cost of shipping should not change.

## Road Freight

Similar to ocean freight, if you’re sending your shipment by road, the shipper will use the greater of its actual weight and volumetric weight to calculate the cost. There are some differences, however.

With road freight, the volume (cbm) is multiplied by a standard multiple – usually 333kgs – to create the volume weight. Cost is then calculated on a fixed rate sliding scale and will depend on which rate category the higher of the actual weight and volume weight falls within.

For example:

- You’re sending cargo that weighs 400kg.
- The cubic volume (length x breadth x width) of the cargo is 0.769cbm.
- Multiply the cubic volume by 333kgs to get 0.769 x 333kg = 256kg.
- 400 is higher than 256; therefore the actual weight of the shipment is used to calculate the freight charge, depending on where it sits on the sliding scale of charges.

One exception to the rule is if you’re shipping goods which aren’t stackable, e.g. something awkwardly shaped or too heavy to stack on top of other cargo. In this case, you’ll be charged as if your cargo is also taking up the space above it using the dimensions of your base pallet and industry standard trailer dimensions to calculate your cargo’s ‘loading metre value’ in kg.

## Air Freight

Air freight also uses weight and volume to calculate its shipping rates. But, as you’ve probably figured out by now, nothing is simple when it comes to freight costings! If you’re shipping by air, a standard dividing factor of 6000 will also come into play.

For example:

- You’re sending cargo that weighs 0.4kg.
- The cubic volume (length x breadth x width) is 12000 cbcm (cubic centimetres)
- The cubic volume is then divided by 6000 to get 12000 / 6000 = 2kg. 2kg is now the volume weight of the cargo.
- As the volume weight is higher than the actual weight, the volume weight is used to calculate the cost (usually on a per kg basis).
- So, where the freight charge is £10 per kg, the cost of sending this cargo is 2 x £10 = £20.

To make matters even more complicated, some carriers deviate from the standard dividing factor of 6000 – often using 5000 instead.

If just reading this article has made your head hurt, you’re unlikely to be relishing the prospect of calculating and comparing the different costing methods yourself. This is where a freight forwarder like Denholm Good Logistics can make your life much easier. Our customer service agents are experts in all things shipping and will be happy to calculate the cost of sending your cargo by a variety of different methods so that you can make an informed decision – without a headache – or a calculator! Contact our friendly team if you require assistance.