Cartons per container, computed from internal millimetres — not from a paper cbm figure. The engine tests all six carton orientations, refills the leftover end slab, and stops the moment you hit the payload limit.
| Container | Cartons | Util. | Gross kg | Need |
|---|
A 40ft high cube is quoted at 76.4 cbm. Nobody loads 76.4 cbm into one. The internal volume is real, but a carton is a rectangular block that cannot be folded into the gap left over by a loading pattern, so the achievable figure is always lower — typically 75–88% depending on how well your carton dimensions divide into the container's own dimensions.
The difference is not academic. If your carton gets you 900 units into a 40HQ instead of the 840 you assumed, the freight cost per unit falls by 7% before you have negotiated anything.
For every carton it tests six orientations — length along the container's length, width along the length, and every rotation between — against the container's internal dimensions, and keeps the one that yields the most cartons. It then takes the leftover slab at the end of the container and runs a second pass to fill it. Finally it caps the result at the container's payload limit, because a light carton and a dense carton hit completely different ceilings.
| Container | Internal L × W × H | Paper cbm | Payload ceiling |
|---|---|---|---|
| 20ft GP | 5,898 × 2,352 × 2,393 mm | 33.2 | ~28,180 kg |
| 40ft GP | 12,032 × 2,352 × 2,393 mm | 67.7 | ~26,700 kg |
| 40ft HQ | 12,032 × 2,352 × 2,698 mm | 76.4 | ~26,580 kg |
| 45ft HQ | 13,556 × 2,352 × 2,698 mm | 86.0 | ~25,600 kg |
Payload varies by carrier, chassis and road regulation — US inland weight limits often bite before the container's own payload does. Treat the ceiling here as the ocean leg's limit, not the door-to-door one.
A EUR pallet is 1200 × 800 mm with a 144 mm deck. Two of them side by side fill a container's 2,352 mm width with 352 mm to spare, and the deck plus the stack height you can safely build usually leaves 900–1,100 mm of empty air above each pallet in a high cube. That is why a palletised 40HQ often carries 30–40% less cargo than the same cartons floor-loaded.
If your buyer insists on pallets — common for EU distribution centres and Australian retail — cost the freight per unit on the palletised figure. Quoting off the floor-loaded number is how exporters end up absorbing a second container.
Use it to choose a carton size before you place the order — that is where the leverage is. Changing a carton from 500 × 400 × 350 to 500 × 400 × 300 mm can be worth more per container than a 5% freight negotiation.
The calculator gives you the answer. These guides give you the reasoning, so you can tell when the answer is wrong.
Why the nominal cbm on a container spec is not the capacity you get, how packing and the weight ceiling decide the real count, and what pallets cost.
Read the guide → Freight · 6 minThe volumetric weight formula, which divisor applies to air, express and LCL, and how carton density tells you whether you pay for space or weight.
Read the guide →