Published June 28, 2026 · Updated June 28, 2026 · 5 min read
Before you book a freight shipment, you need to know your cargo's volume in cubic meters (CBM). Freight forwarders use CBM to quote LCL rates, calculate container utilization, and determine chargeable weight for air freight. Getting it wrong leads to surprise charges. Here's how to calculate it correctly.
CBM stands for Cubic Meter. It's the international standard unit of volume for shipping cargo. One CBM is a cube measuring 1 meter × 1 meter × 1 meter (roughly 35.3 cubic feet).
Freight is priced by CBM in two scenarios:
CBM = Length (m) × Width (m) × Height (m) × Number of CartonsIf you measure in centimeters, convert first: divide each dimension by 100 to get meters.
You're shipping 200 cartons. Each carton measures 50cm × 40cm × 30cm.
CBM Calculator — enter your carton dimensions and quantity to instantly get total CBM, weight, and container utilization.
| Container Type | Usable CBM | Max Payload |
|---|---|---|
| 20GP (20-foot standard) | 25–28 CBM | ~21,700 kg |
| 40GP (40-foot standard) | 55–58 CBM | ~26,500 kg |
| 40HQ (40-foot high cube) | 68–72 CBM | ~26,500 kg |
In practice, achieving 100% container utilization is rare due to carton stacking limits and irregular shapes. Aim for 85–90% fill rate when planning.
Carriers charge based on whichever is greater: actual weight or volumetric weight.
| Mode | Volumetric Weight Formula |
|---|---|
| Air freight | CBM × 167 = volumetric weight (kg) |
| Sea freight (LCL) | CBM × 1,000 = volumetric weight (kg) |
| Express (DHL/FedEx/UPS) | L(cm) × W(cm) × H(cm) ÷ 5,000 = kg |
Why this matters: if your goods are lightweight but bulky (e.g., foam padding, empty boxes), volumetric weight will exceed actual weight — and you'll pay for the larger number. Dense products (metal parts, electronics) are the opposite: actual weight dominates.
The crossover point varies by route and season, but if your CBM is above 15, get FCL quotes alongside LCL — FCL often wins.
CBM stands for Cubic Meter, the standard volume unit for international freight. Carriers use it to price LCL shipments and calculate volumetric weight for air cargo.
Multiply length × width × height (in meters) per carton, then multiply by the number of cartons. Convert centimeters to meters by dividing by 100.
A 20GP container holds approximately 25–28 CBM of usable cargo space. A 40GP holds 55–58 CBM.
The higher of actual weight vs volumetric weight. For air freight, volumetric weight = CBM × 167 kg. You are always billed on the greater value.