How CBM is calculated
CBM (cubic meters) is the volume of your shipment. Multiply the carton length by the width by the height, then multiply by the number of cartons. In metric units, divide cubic centimeters by 1,000,000. In imperial units, divide cubic inches by 61,024.
Example: one carton measures 60 × 50 × 40 cm. That is 60 × 50 × 40 = 120,000 cm³, or 0.12 CBM per carton. For 100 cartons, the total is 0.12 × 100 = 12 CBM.
Container capacity at a glance
These are typical ISO internal volumes and max payloads. Carriers vary slightly, and real loadable volume is always lower because cartons never pack perfectly.
| Container | Volume / max payload |
|---|---|
| 20GP | 33.2 CBM / 28,200 kg |
| 40GP | 67.7 CBM / 26,800 kg |
| 40HQ | 76.4 CBM / 26,500 kg |
What to check before you book
Volume decides the container; weight can still stop you. A 20GP holds 33.2 CBM, but if your cargo is heavy — more than 1,000 kg per CBM — the payload limit binds first. Sea freight is usually charged per CBM; heavy cargo may be charged by weight instead.
Leave a margin. Plan on 25–28 CBM of usable space in a 20GP and 55–65 CBM in a 40HQ. The gap covers packing gaps, pallets, and cartons that do not stack neatly.