CBM meaning in shipping
CBM is short for cubic metre, written m³. One CBM is the space taken by a box that measures 1 m × 1 m × 1 m. Shippers, forwarders and carriers use it as the standard way to describe how much space cargo occupies.
You will see CBM on packing lists, booking requests, LCL rate sheets and container specifications. A carton, a pallet, a whole consignment and a container's inside can all be described in CBM, which makes it easy to compare them.
Why CBM matters
- Quoting. LCL sea freight is charged per CBM or per tonne, whichever is greater. Air and courier carriers turn the volume into a volumetric weight.
- Choosing a container. A 20ft container holds about 33 CBM and a 40ft high cube about 76 CBM, before allowing for the gaps that cartons leave.
- Planning space. Warehouses, pallets and trucks all have limited space, and CBM lets you compare your cargo with it.
- Cost per unit. When freight is shared between products, volume is often the fairest way to split it.
How big is one CBM?
One cubic metre equals 1,000 litres, 1,000,000 cm³ or about 35.31 cubic feet. As a rough picture, a standard washing machine box is around 0.3 CBM, so about three of them make one cubic metre.
| Item | Approximate volume |
|---|---|
| Shoe carton 60 × 40 × 35 cm | 0.084 CBM |
| Euro pallet loaded to 1.8 m (1.2 × 0.8 m) | 1.73 CBM |
| 20ft container (inside) | about 33 CBM |
| 40ft high cube container (inside) | about 76 CBM |
CBM is volume, not weight
CBM says nothing about how heavy cargo is. One CBM of pillows and one CBM of steel bolts take the same space but weigh very different amounts. That is why carriers compare volume with weight before deciding what to charge, as explained in CBM vs volumetric weight. The ratio of the two is the cargo's density, which the Freight Density Calculator works out.
Working out your CBM
For a single box, multiply its length, width and height in metres. For a shipment, multiply by the number of boxes and add up every carton size. The step-by-step method, with examples in centimetres, millimetres and inches, is in How to Calculate CBM, and the CBM Calculator does it for any mix of cartons.