CBM (Cubic Metre) Calculator
Calculate the total cubic volume of a shipment in CBM (m³) and CFT (ft³), and estimate how many 20ft or 40ft shipping containers are needed.
Results
What is it?
CBM (Cubic Metre) is the standard unit of volume measurement in international freight. It determines how much space your goods occupy in a container, truck, or air freight consignment. Freight is charged on either actual weight or volumetric (dimensional) weight — whichever is higher. For sea freight, CBM drives the cost; for air, dimensional weight often dominates. Container usable capacities: 20ft = 25.45 m3; 40ft standard = 56.1 m3; 40ft High Cube = 67.7 m3.
How to use
Enter the outer dimensions of one carton in centimetres and the total number of cartons. The calculator converts cm to metres automatically (divides each dimension by 100) and multiplies for CBM per unit, then multiplies by quantity. Results show total CBM, CFT equivalent, and fractional container requirements.
Example scenario
A shipment of 100 cartons, each 60x40x30 cm: CBM per carton = 0.6 x 0.4 x 0.3 = 0.072 m3. Total = 0.072 x 100 = 7.2 m3. That requires approximately 7.2 / 25.45 = 0.28 of a 20ft container, so the shipment would be grouped with other cargo as an LCL (Less than Container Load) shipment.
Pro tip
Always measure outer carton dimensions (not inner product dimensions) and add 1-2 cm tolerance for packaging deformation under load. For volumetric weight in air freight, use: (L x W x H in cm) / 6,000 = volumetric kg per carton. If volumetric weight exceeds actual weight, you pay for volumetric.