A 20ft standard container is roughly 33 m³ inside, but that is not a guaranteed carton capacity. Hapag-Lloyd lists one example at 590 × 235.2 × 239.5 cm and 33.2 m³. Use the actual equipment dimensions, usable clearance and payload to estimate a shipment.
Which dimensions should you measure?
The nominal 20ft label identifies the container class. It is not the usable internal length. Measure or confirm the inside length, width and height, then check the door opening separately. A rigid unit can fit inside a container yet fail to pass through its door.
Hapag-Lloyd describes its specifications as fleet examples that vary by manufacturer. The table distinguishes those published figures from the editable preset in this calculator; neither should replace the specification of your assigned container.
| Item | Carrier example | Planner preset |
|---|---|---|
| Internal length | 590 cm / 5.90 m | 589 cm / 5.89 m |
| Internal width | 235.2 cm / 2.352 m | 235 cm / 2.35 m |
| Internal height | 239.5 cm / 2.395 m | 239 cm / 2.39 m |
| Internal volume | 33.2 m³ listed | 33.08 m³ calculated |
| Payload | 28,130 kg | 28,200 kg |
| Door opening, W × H | 234 × 229.2 cm | Verify separately |
How many 60 × 40 × 30 cm cartons fit?
For a transparent hand calculation, use the planner preset with 10 cm reserved at the door end and 5 cm below the roof. That leaves 579 cm of length and 234 cm of height. Keep every carton in the same orientation, with 60 cm along the container, 40 cm across it and 30 cm upright.
The grid contains 9 × 5 × 7 = 315 cartons. At 15 kg each, that is 4,725 kg and 22.68 m³ of cartons. This is an illustrative grid, not a claim that the automatic solver will return exactly 315 or that no better arrangement exists.
floor(579 ÷ 60) × floor(235 ÷ 40) × floor(234 ÷ 30) = 315
Why does 33 m³ not mean 33 m³ of cartons?
Whole carton dimensions leave narrow strips and space above the last full layer. Dividing the preset volume by 0.072 m³ per carton gives a loose upper bound of 459 cartons before clearance, weight and geometry. The grid example shows why that volume-only figure is not an achievable loading promise.
Use packaged outside dimensions, including bulging cartons or protection. If freight travels on pallets, enter the loaded pallet envelope rather than the bare product dimensions. Record these assumptions so a colleague can reproduce the estimate.
What should you verify before using the plan?
Set the permitted rotation and the actual stacking limit. The calculator does not infer carton compression strength from gross weight. Confirm payload, floor loading, securing space and transport-route restrictions independently. The IMO/ILO/UNECE CTU Code provides packing and securing guidance; it does not certify an individual software layout.
- Confirm the assigned container and door opening.
- Use gross packed weight, including packaging.
- Keep space needed for dunnage, securing and access.
- Review unplaced cartons and export the final input rules with the result.
Open the load planner
Use your actual carton dimensions, weight and stacking rules to turn this example into a checked layout.
Start planningFAQ
Is a 20ft container always 33.2 CBM?
No. That is one published equipment example. Internal dimensions and specifications vary; the editable tool preset calculates approximately 33.08 m³.
Can I use 20ft external dimensions in the planner?
No. Enter usable internal dimensions. Check the physical door opening independently because the planner does not simulate doorway traversal.