20-ft Container

What it means

The international standard ISO 668 classifies series 1 freight containers by external dimensions and sets their ratings, and for some types it sets minimum internal and door opening dimensions. The current edition is ISO 668:2020, amended in 2022.^[1] Within those rules, each container's inside size, empty weight and payload depend on how it was built, so published figures are typical, not guaranteed.

The Federal Highway Administration describes the 8 x 8 x 20 ft container as the basic measure in container statistics, the TEU.^[3] Maersk's specification for its 20ft standard steel dry container lists 33 m³ (1,165 cu ft) of volume and a 28,200 kg (62,170 lb) maximum payload, only 600 kg less than its 40ft box.^[2] That is why heavy cargo usually fills a 20 by weight before it fills it by volume; see why heavy cargo ships in 20ft containers.

20ft container dimensions

Typical figures for a 20ft standard dry container from one carrier's published sheet. Confirm against the plate and markings on the box you receive.^[2]

How many cubic meters in a 20ft container?

The nominal figure is 33 m³.^[2] Multiplying the inside dimensions (5.896 x 2.35 x 2.393 m) gives about 33.2 m³. Real loads use less: pallet decks, gaps between cartons, bracing and the clearance needed to close the doors all take space. For dense goods the question is often moot, because the payload is reached long before the box is full. One cubic meter is about 35.3 cubic feet.

How many pallets fit in a 20 foot container?

Divide the floor (5,896 x 2,350 mm) by the pallet footprint.^[2] A 48 x 40 in. U.S. pallet is about 1,219 x 1,016 mm and a Euro pallet is 1,200 x 800 mm. For one tier with no overhang:

• 8 standard pallets, loaded straight. Two across, four rows deep (4 x 1,219 = 4,876 mm), leaving about 1 m at the door.
• 9 standard pallets, mixed. Five turned in one row beside four straight in the other, using 2,235 mm of the 2,350 mm width. It needs pallets with no overhang.
• 11 Euro pallets. Seven turned beside four straight.
• Stacking. A second tier must clear the 2,274 mm door opening and keep the total under the 28,200 kg payload.

The container vs. trailer capacity guide shows the same math for 40s and 53-ft trailers.

20ft container max weight

On the Maersk sheet, the 20ft box weighs 2,280 kg empty, takes up to 28,200 kg of cargo and is rated at 30,480 kg (67,200 lb) maximum gross.^[2] On U.S. roads a second limit applies: federal rules cap a vehicle on the Interstate System at 80,000 lb gross, with 20,000 lb on a single axle and 34,000 lb on a tandem.^[4] A 20 at full rated gross leaves 12,800 lb for the tractor and chassis together. Weight also concentrates over a short footprint, so how the load sits in the box matters for axle weights; see the bridge formula. The shipper must also declare the packed container's verified gross mass before it is loaded on a vessel.

Why it matters

A 20 loaded to its rating can be legal at sea and still too heavy for the chassis and road. If a container has to be lightened before it moves inland, RapidShips devans 20, 40 and 45 ft containers and handles overweight correction at its East Brunswick, NJ dock, about 30 road miles from the Port Newark–Elizabeth terminals.

Example

Hypothetical: an exporter ships ceramic tile on eight 48 x 40 in. pallets of 1,500 kg each, 12,000 kg in total. The pallets cover the floor of a 20 in two rows of four and use well under half its 33 m³, but the weight is already about 43% of the 28,200 kg payload. Even stacked two high, 16 pallets would weigh 24,000 kg, about 85% of the payload. A 40 carries only 600 kg more on the same carrier's sheet, so the exporter books more 20s rather than paying for a box it cannot fill by weight.

Frequently asked questions