20 ft vs 40 ft container: how many cartons fit?
When an import order grows past a few pallets, the question becomes which container to book. The answer depends on your carton size, how heavy the goods are and whether the extra space of a 40 ft is worth it.
Container dimensions
| Container | Inside (L × W × H) | Volume | Typical max payload |
|---|---|---|---|
| 20 ft | 5.90 × 2.35 × 2.39 m | about 33 m³ | about 28,000 kg |
| 40 ft | 12.03 × 2.35 × 2.39 m | about 67 m³ | about 26,700 kg |
| 40 ft high cube | 12.03 × 2.35 × 2.69 m | about 76 m³ | about 26,500 kg |
Figures vary by container and operator. Road weight limits in the origin and destination country may be lower than the container's own payload.
Estimating cartons per container
Divide each inside dimension by the carton dimension, round down, and multiply. Then try the carton in other orientations. For a 60 × 40 × 40 cm carton in a 20 ft container: 590 ÷ 60 = 9, 235 ÷ 40 = 5, 239 ÷ 40 = 5, so 225 cartons. Turned 90°: 590 ÷ 40 = 14, 235 ÷ 60 = 3, 239 ÷ 40 = 5, so 210. The first orientation wins.
A 40 ft holds roughly twice as many, and a high cube adds another layer if the carton height divides well into the extra 30 cm.
Volume vs weight
A 40 ft container doesn't carry twice the weight of a 20 ft; the payloads are similar. That makes 20 ft containers popular for heavy goods like tiles, metal parts or liquids, which reach the weight limit well before the container is full. Light goods, like packaging, furniture or textiles, are the opposite: they fill 40 ft and high cube containers efficiently.
Which is cheaper?
A 40 ft usually costs much less than twice a 20 ft, so the cost per cubic meter is lower. If your goods are light enough and you have the volume, the 40 ft is typically the better value. If you're only just over 20 ft capacity, compare a 40 ft with a 20 ft plus an LCL shipment.
Palletized or floor loaded?
Floor loading cartons directly fits more in, because pallets take space and don't match container widths well. Palletized loading is faster to unload and easier on the goods. Many importers floor load and palletize at the destination warehouse.