Start with the equipment, then calculate the load
A 20 ft container’s cubic capacity is a volume envelope, not a carton count. Hapag-Lloyd’s example 20 ft standard container lists 5.900 m × 2.352 m × 2.395 m inside dimensions and 33.2 CBM capacity. Its door opening is smaller: 2.340 m wide × 2.292 m high. The carrier says these are example specifications and equipment varies by manufacturer.
The calculation below uses those example inside dimensions and fictional cartons measuring 60 × 40 × 40 cm externally. It assumes floor loading without pallets. It is an arithmetic demonstration, not an approved loading plan.
Calculate each carton’s CBM
Convert centimeters to meters: 60 × 40 × 40 cm becomes 0.60 × 0.40 × 0.40 m. One carton occupies 0.096 CBM. Five cartons occupy 0.480 CBM. A proposed 225-carton shipment occupies 21.600 CBM.
Dividing the listed 33.2 CBM by 0.096 gives approximately 345.8 carton volumes. Rounding down to 345 does not establish that 345 whole boxes fit: the calculation has ignored their shape, orientation and all operating space.
| Quantity | Calculation | Total volume |
|---|---|---|
| 1 | 0.60 × 0.40 × 0.40 | 0.096 CBM |
| 5 | 5 × 0.096 | 0.480 CBM |
| 225 | 225 × 0.096 | 21.600 CBM |
Count whole cartons in two simple orientations
In a uniform grid with the 60 cm edge along the container length, floor(5.900 ÷ 0.60) = 9 cartons fit along the length. Across the width, floor(2.352 ÷ 0.40) = 5. In height, floor(2.395 ÷ 0.40) = 5. That grid contains 9 × 5 × 5 = 225 cartons.
Rotating the floor footprint to 40 cm along the length and 60 cm across the width gives 14 × 3 × 5 = 210 cartons. The box volume has not changed, but the simple grid count has.
| Carton orientation (L × W × H) | Whole-carton counts | Grid result |
|---|---|---|
| 0.60 × 0.40 × 0.40 m | 9 × 5 × 5 | 225 cartons |
| 0.40 × 0.60 × 0.40 m | 14 × 3 × 5 | 210 cartons |
Why 225 is a demonstrated grid, not the maximum load
A mixed-orientation layout may use space more effectively than either uniform grid. Conversely, carton tolerances, bulging, dunnage, handling clearance, stacking strength and lashing may require fewer boxes. This example does not optimize mixed layouts or certify that a crew can load them safely.
Do not replace the calculation with an arbitrary utilization percentage and call that a verified fit. Keep a drawing or loading sequence, check the actual container’s door and interior, and account for packaging and securing materials. A preassembled stack must also pass through the door.
Check weight and stacking separately
If each fictional carton weighs 15 kg gross, 225 cartons weigh 3,375 kg before pallets, dunnage or other packing materials. Compare the full load against the assigned container’s plate and the transport limits that apply to the route; a volume result alone does not settle those checks.
Five layers put four cartons above the bottom carton in a vertical column. Verify packaging compression strength, allowed orientations and handling instructions before assuming that stack is suitable.
Reproduce the calculation
Use the related Cargoivo calculator with your own shipment dimensions, weight, or quantity.
Open Container Loading Calculator →Cargoivo provides educational planning information, not a freight quote, engineering approval, customs advice, or carrier commitment. Verify current service rules, equipment specifications, and commercial terms before shipping.