What Is CBM, and How Is It Calculated?

The word "CBM" is frequently used to transport commodities from one nation to another via air, sea, or land. Short for "cubic meter," CBM is a widely used unit of measurement in shipping and determines how much you pay for freight.

We've gathered all the information you want about CBM in this article so that you may precisely measure your cargo and calculate your shipping expenses. Read on to learn:

• What is the meaning of CBM?

• How do you calculate CBM?

• What are Volumetric Weight and Chargeable Weight?

• How do you calculate freight using CBM for ocean, air, and road shipments?

• How does CBM impact containers and pallets?

• How is the CBM of cylindrical and irregular containers calculated?

• How does CBM impact freight cost?

What is the meaning of CBM?

A cubic meter, or CBM, measures a shipment's volume. It indicates how much space your goods will require on a ship, airplane, or truck and how much it will cost to transport.

How do you calculate CBM?

Length x Width x Height = CBM

This is the formula used to measure your cargo volume in CBM (m³).

Say you have a carton 2 meters long, 2 meters wide, and 2 meters high. Then, its volume is 2 x 2 x 2 = 8 m³.

And if you have ten such identical cartons in a single consignment, you can multiply the CBM by the total number of cartons to arrive at the full volume – 8 x 10 = 80 m³.

If the cartons are not the same size, calculate the CBM for each carton by using the same formula and adding up the total.

"There is enough energy in a single cubic meter of space to boil all the oceans in the world." – Richard P. Feynman.

What are Volumetric Weight and Chargeable Weight?

In shipping, volume (CBM) is one way of calculating freight. The other is weight. Traditionally, the importance of a shipment is said to decide its transportation cost. But what if the consignment is extremely light but has a large volume (a carton of styrofoam cups or a bale of cotton wool, for example)? Such a shipment would take up more space than a load of small steel items. But if freight is charged based on its lightweight, the amount would be nominal. This is where a concept called dimensional or volumetric weight and the chargeable weight come in.

Gross Weight: This is the actual weight of your cargo, including any packaging, cushioning, and pallets.

Dimensional/Volumetric Weight: The cargo volume converted into its weight equivalent (CBM to kg) is called dimensional or volumetric weight. Depending on the freight mode (air, sea, road) and carrier, dimensional weight can be calculated using either of these formulas:

1. CBM x DIM Factor = Dimensional Weight

2. Length (cm) x Width (cm) x Height (cm) x Quantity / DIM Factor = Dimensional Weight

Quantity is the number of packages that makes up a single cargo consignment.

The DIM factor, or dimensional weight factor, varies according to freight mode (sea, air, courier, truck) and carrier. Generally accepted DIM factors are:

• Sea freight – 1:1,000 (1 m³ = 1,000 kg or 1 ton)

• Air freight – 1:6,000 (1 m³ = 6,000 kg or 6 tons). But when we use the first formula (CBM x DIM Factor = Dimensional Weight), the DIM factor is 1:167, where one m³ = 167 kg.

• Courier/Express freight – 1:5,000 (1 m³ = 5,000 kg or 5 tons)

• Road freight (less than truckload or LTL) – 1:3,000 (1 m³ = 3,000 kg or 3 tons.

Note: Though the DIM factors mentioned here are widely accepted, they might still vary across freight modes, service providers, and regions, so check what is applicable in your case.

Chargeable weight: Once you have both your gross and dimensional weight, your freight service provider will charge you based on whichever is more excellent. You will be charged based on the former if the gross weight exceeds the dimensional weight. But if the dimensional weight is more significant, that will be the chargeable weight. This is called chargeable weight.

How do you calculate freight using CBM for ocean, air, and road shipments?

1. For LCL ocean freight

Say you are sending a less-than-container load (LCL) shipment by sea. (LCL shipping is a mode of transporting moderate cargo volumes in a shared container). Shipping lines charge freight based on CBM, primarily for LCL shipments, provided they weigh less than one ton (1,000 kg). If the cargo weighs over a ton, freight is charged based on weight.

Example 1

Package dimensions: 4 m x 4 m x 4 m

CBM: 4 x 4 x 4 = 64 m³

DIM factor: 1:1,000

Gross weight: 200 kg (0.2 ton)

Freight rate: $50 per CBM/ton

Since volume (CBM) exceeds the actual weight, freight will be charged based on CBM.

Hence, freight cost: 50 x 64 = $3,200

Example 2

Package dimensions: 2 m x 2 m x 1 m

CBM: 2 x 2 x 1 = 4 m³

DIM factor: 1:1,000

Gross weight: 5,500 kg (5.5 tons)

Freight rate: $50 per CBM/ton

Since gross weight is greater than volume, freight will be charged based on gross weight. Hence, freight cost: 50 x 5.5 = $275

2. For air freight

Here, we have used the second formula to calculate dimensional weight – Length (cm) x Width (cm) x Height (cm) / DIM factor – and a DIM factor of 1:6,000 to arrive at freight cost.

Example 1

Freight rate: $150 per CBM/ton

Package dimensions: 150 cm X 100 cm X 100 cm

Gross weight: 200 kg (0.2 ton)

Dimensional weight: 150 x 100 x 100 / 6,000 = 250 kg (0.25 ton)

Chargeable weight is the dimensional weight (250 kg) greater than the gross weight (200 kg). Hence, freight cost: 0.25 x 150 = $37.50

Example 2

Freight rate: $150 per CBM/ton

Package dimensions: 50 cm X 80 cm X 60 cm

Gross weight: 1,200 kg (1.2 tons)

Dimensional weight: 50 x 80 x 60 / 6,000 = 40 kg (0.04 ton)

Chargeable weight is the gross weight (1,200 kg), greater than the dimensional weight (40 kg). Hence, freight cost: 1.2 x 150 = $180

3. For road (truck LTL) freight

This calculation is based on the formula Length (cm) x Width (cm) x Height (cm) / DIM factor for dimensional weight, using a DIM factor of 1:3,000.

Freight rate: $60 per CBM/ton

Package dimensions: 150 cm x 80 cm x 60 cm

Dimensional weight: 150 x 80 x 60 / 3,000 = 240 kg (0.24 ton)

Gross weight: 175 kg (0.175 ton)

Dimensional weight (240 kg), greater than gross weight (175 kg), is the chargeable weight. Hence, freight cost: 0.24 x 60 = $15

Note: Freight rates mentioned in the examples above are representative. Contact your freight forwarder and/or CHA for actual and current rates.

How many CBMs are in a container?

With numerous of us using containers to ship our goods, intravital to know how many CBMs can be accommodated in a standard 20-foot, 40-foot, and 45-foot container:

Note: HC means High Cube; Payload is the maximum cargo weight a container can hold

How many CBMs are in a pallet?

Like containers, pallets – flat structures used to support and secure cargo – come in standard sizes. The most common ones are the 48’’ x 40’’, 42’’ x 42’’, and 48’’ x 48’’1 pallets. One of these standard pallets can accommodate 1.26 m³.

How do you calculate CBM for irregularly shaped packages?

All the dimensions and calculations mentioned in this article have been for packages with a regular shape, such as a cube or cuboid. A carton is a package with a standard form, for which the formula is Length x Width x Height = CBM. But what if your parcel has an irregular shape? How do you measure its CBM?

1. Cylindrical package: A rolled carpet or a pipe. Set the package upright and measure its height and radius (half its diameter). Measurements should be in meters. Now use the formula π x r ² x h = CBM, where

• π is the symbol for pi, which is the ratio of the circumference to the diameter of a circle, conventionally equal to 3.14

• r is the radius

• h is the height (which is equal to the length)

2. Irregularly shaped package: To measure the CBM of such a package, measure its most extended length, longest Width, and most extended height. Then use the formula Length (max) x Width (max) x Height (max) = CBM.

Measurements and conversions

Since CBM is calculated in meters, here is how you can convert your cargo measurements into meters:

• Foot to meter: 1 foot equals 0.3048 meters, so multiply the foot value by 0.3048

• Inch to meter: 1 inch equals 0.0254 meters, so multiply by 0.0254

• Centimeter to meter: 1 centimeter equals 0.01 meters, so multiply by 0.01

How does CBM impact freight cost?

When we say that cargo volume or CBM determines your freight cost, weren't talking about the carrier charges for transporting your goods. When you receive a freight quote, it includes many other charges and surcharges, all or some of which might also be calculated based on CBM. These include:

• Terminal handling charges: These are costs associated with equipment and property owned by terminals at the origin and destination and the use of labor provided for the loading/unloading of cargo and their transport.
  

• Inland haulage charges are costs associated with cargo movement from the inland container depot/container freight station to the loading port or vice-versa.

• Bunker Adjustment Factor (BAF): The fuel Adjustment Factor is an additional charge levied on carriers to account for fuel price fluctuations.

Currency Adjustment Factor (CAF): This is a surcharge levied by carriers to compensate for currency rate fluctuations to the base exchange rate.

Have you found the methods outlined in this article helpful? Let us know in the comments and join the conversation on finding the most effective ways to determine freight costs.