Shipping Container Sizes and Loading Capacity

Common dry-container choices

A 20-foot dry container is often selected for dense cargo. Maersk lists approximately 33.2 m³ capacity and a 28,300 kg maximum payload for its standard steel example.

A standard 40-foot dry container provides about 67.7 m³, while a 40-foot high cube increases height and lists about 76.4 m³. Payload limits remain separate from volume capacity.

Nominal size is not usable size

The name 20-foot or 40-foot describes the equipment class, not an exact empty rectangular space. Internal dimensions, door openings, corrugations, lashing points, and manufacturer tolerances affect a load.

Cartons also leave unused strips when their dimensions do not divide evenly into the container. A volume-only CBM division is therefore an upper bound, not a packing plan.

Before confirming a booking

Confirm the assigned equipment specification, door clearance, cargo weight, legal road limits, floor loading, blocking and bracing, moisture protection, and destination requirements.

For palletized cargo, model cartons on the pallet first, then pallets in the container. For loose cartons, consider load sequence and unloading access as well as maximum count.

Compare the presets on the same basis

The table separates published example capacity and payload from the rounded internal dimensions used by this calculator. The product of the rounded dimensions is not exactly the published capacity. Use the dimensions for grid arithmetic and the assigned equipment specification for a booking.

The 40 ft example offers about 2.04 times the nominal volume of the 20 ft example, but only about 1.02 times its payload. Doubling carton volume does not double the allowable cargo weight. These are example equipment values, not fleet-wide guarantees.

• Maersk example equipment flyer, checked October 10, 2026