Shipping Container Size Table
| Spec | 20 ft | 40 ft | 40 ft high cube |
|---|---|---|---|
| External length | 19 ft 10.5 in (6.06 m) | 40 ft (12.19 m) | 40 ft (12.19 m) |
| External width | 8 ft (2.44 m) | 8 ft (2.44 m) | 8 ft (2.44 m) |
| External height | 8 ft 6 in (2.59 m) | 8 ft 6 in (2.59 m) | 9 ft 6 in (2.90 m) |
| Internal length | 19 ft 3 in (5.87 m) | 39 ft 4.4 in (12.00 m) | 39 ft 4.4 in (12.00 m) |
| Internal width | 7 ft 7.75 in (2.33 m) | 7 ft 7.75 in (2.33 m) | 7 ft 7.75 in (2.33 m) |
| Internal height | 7 ft 8.5 in (2.35 m) | 7 ft 8.5 in (2.35 m) | 8 ft 8.5 in (2.65 m) |
| Internal volume | 33.1 m³ (1,169 cu ft) | 67.5 m³ (2,385 cu ft) | 75.3 m³ (2,660 cu ft) |
| Tare weight | 2,200 kg (4,850 lb) | 3,800 kg (8,380 lb) | 3,935 kg (8,675 lb) |
| Max gross weight | 30,480 kg (67,200 lb) | 33,000 kg (73,000 lb) | 30,480 kg (67,200 lb) |
| Typical net load | 28,280 kg (62,350 lb) | 26,680 kg (58,820 lb) | 26,545 kg (58,522 lb) |
Three boxes move almost everything: the 20 ft, the 40 ft, and the 40 ft high cube. All share an 8-foot width (2.44 m) - a hard limit inherited from road transport law, which is also why no standard container ever got wider - and differ in length and, for the high cube, a 12-inch height bump (9 ft 6 in over 8 ft 6 in) that adds roughly a quarter more volume. The 20 ft is the unit of account of world trade: TEU (twenty-foot equivalent unit) counts port throughput, and a 40 ft box is a FEU, two TEU on paper but one box in the yard.
The weight rows hide the real decision. A 20 ft box weighs less empty (about 2,200 kg) but carries more: around 28,000 kg of payload - it is the heavy-cargo box, and dense freight (machinery, liquids, ingots) cubes out its 33 cubic meters long before it runs out of weight allowance. The 40 ft boxes weigh more empty (3,800-3,900 kg) and legally carry slightly less payload (about 26,500 kg) but offer 67.5 and 75.3 cubic meters - the light-and-bulky box. Furniture, clothing and consumer goods ship 40 ft; steel and stone ship 20 ft; the cube rating of your cargo decides which box you rent.
How to use
- Size the box to the cargo's cube-vs-weight profile: compute your load's volume and weight, then compare - over about 28 tonnes means a 20 ft; over 33 cubic meters means at least a 40 ft; over 60 cubic meters needs the high cube.
- Check the door, not just the box: the door aperture is smaller than the internal dimensions (about 2.28 m wide by 2.26 m tall on a 20 ft), so loading plans live or die at the opening.
- Verify against the CSC plate: the safety-approval plate riveted to the door carries that specific box's legal gross limit and inspection dates - the table's numbers are typical fleet values, the plate is the law for the box in front of you.
Frequently asked questions
What is the difference between TEU and FEU?
TEU - twenty-foot equivalent unit - is the counting unit of containerized trade: one 20 ft container is one TEU, a 40 ft is a FEU (forty-foot equivalent) and counts as two TEU. The unit measures ship capacity, crane moves and port throughput, not cargo: a single 40 ft box moves as one physical unit but adds two to the TEU statistics, and the port charges the shipping line per move regardless of box length. For a shipper the distinction is mostly about planning language - freight quotes and capacity reports speak in TEU - while your actual booking is for a named box type (20 ft dry, 40 ft high cube, 40 ft refrigerated). The trap hiding in the unit: two TEU of capacity is not two TEU of cargo, because the 20 ft boxes those TEU represent carry 1.5 tonnes more payload each than a 40 ft does.
Why is container width always 8 feet while heights and lengths vary?
Because the width is set by the road, not by the ship. ISO standard containers kept the 8-foot (2.438 m) envelope from their 1950s American trucking ancestors, and global road regulations (a practical 2.5 to 2.6 m vehicle-width ceiling in most countries) mean a wider box could not legally travel to or from the port anyway. Everything else flexes: length comes in 20, 40 and 45 ft ISO plus 48 and 53 ft American domestic sizes that never leave North American roads and rails, and the high cube variants add exactly 12 inches of height for about 13-16 percent more volume at the same footprint. Growth has therefore been vertical and longitudinal for seventy years - a 53 ft high cube domestic box offers 108 cubic meters against the 20 footer's 33 - while the width stays a constant that every truck, rail well car, crane spreader and stack in the world is built around.
Can I load a container to its maximum gross weight?
Rarely, and the chain of limits decides. The 20 ft row says 30,480 kg gross, but subtract the tare (about 2,200 kg) and the payload is 28,280 kg - and then the other links take over: the truck chassis and local road law (in the US, about 44,000-44,500 lb on a tri-axle chassis, inside an 80,000 lb total limit), the crane spreader rating, and the ship's lashing plan. This is why a 40 ft box legally carrying 26,700 kg of cargo can be over-the-road illegal in some jurisdictions while a 20 ft with the same tonnage is fine - the domestic leg governs. For international moves the CSC plate and the carrier's VGM (verified gross mass) declaration are the binding numbers: shippers must verify and document the full packed weight before the box is loaded, and an under-declared heavy box is the classic cause of collapsed container stacks.
What are 48 ft and 53 ft containers, and why only in North America?
They are the domestic exception: bigger boxes built to the internal clearances of US highways and rail well cars, not to ISO sea standards. A 53 ft high cube offers about 108.5 cubic meters - 44 percent more than a 40 ft high cube - at a similar tare, which is why US domestic intermodal freight ( Walmart-style distribution) standardized on it: more boxes of light goods per train, fewer moves per pallet-load. They cannot stack to ISO limits on cell-guided ships and their corners do not match ISO lifting and securing fittings, so they travel inland on dedicated rail cars and trucks, and they show up at ports only in domestic transfer service. Europe, with narrower road envelopes, never adopted an equivalent - its extra capacity came from high-cube 45 ft boxes that stay within ISO width. The lesson in the table: container size follows infrastructure, and the 8-foot ISO family is just one infrastructure's answer.