Shipping Container Dimensions: 10, 20, 40 & 45 ft Size Chart

A shipping container's name — 10 ft, 20 ft, 40 ft, or 45 ft — is the nominal length, not the space you can use. Three measurements decide whether a load, a rack, or a delivery truck will fit: the external size, the internal size, and the door opening. External size is what you plan a pad, a permit, and a truck around. Internal size is the clear space inside the walls. The door opening is smaller than the interior, and it is the measurement that stops a load.

The figures on this page are typical planning numbers for dry ISO containers. Wall thickness, flooring, repairs, and modifications such as insulation, a roll-up door, or a reefer unit change the usable space. Before you load or build out a unit, confirm the CSC safety plate and the spec sheet for that exact container.

Shipping container size chart

ISO containers share one fixed external width: 8 ft (2.44 m). Length and height are what change. A 20 ft container is not 20 ft 0 in long on the outside. Its external length is 19 ft 10.5 in (6.06 m). A 40 ft container is 40 ft 0 in (12.19 m) outside. Standard exterior height is 8 ft 6 in (2.59 m). High cube exterior height is 9 ft 6 in (2.90 m).

Size	External (L × W × H)	Internal (L × W × H)	Door opening (W × H)	Usable volume	Typical payload
10 ft standard	10 ft × 8 ft × 8 ft 6 in	9 ft 3 in × 7 ft 8 in × 7 ft 10 in	7 ft 6 in × 7 ft 5 in	about 560 cu ft	Check the CSC plate
20 ft standard	19 ft 10.5 in × 8 ft × 8 ft 6 in	19 ft 4 in × 7 ft 8 in × 7 ft 10 in	7 ft 8 in × 7 ft 6 in	about 1,170 cu ft (33.1 m³)	about 47,900 lb (21,700 kg)
20 ft high cube	19 ft 10.5 in × 8 ft × 9 ft 6 in	19 ft 4 in × 7 ft 8 in × 8 ft 10 in	7 ft 8 in × 8 ft 5 in	about 1,320 cu ft	Close to a 20 ft; check the plate
40 ft standard	40 ft × 8 ft × 8 ft 6 in	39 ft 5 in × 7 ft 8 in × 7 ft 10 in	7 ft 8 in × 7 ft 6 in	about 2,390 cu ft (67.7 m³)	about 59,040 lb (26,780 kg)
40 ft high cube	40 ft × 8 ft × 9 ft 6 in	39 ft 5 in × 7 ft 8 in × 8 ft 10 in	7 ft 8 in × 8 ft 5 in	about 2,700 cu ft (76 m³)	about 58,080 lb (26,350 kg)
45 ft high cube	45 ft × 8 ft × 9 ft 6 in	44 ft 4 in × 7 ft 8 in × 8 ft 10 in	7 ft 8 in × 8 ft 5 in	about 3,040 cu ft	Often near a 40 ft; check the plate

Payload figures are working numbers for many dry boxes still in service. Newer units are often rated to a higher maximum gross mass (30,480 kg, and some to 36,000 kg). The CSC plate on the container is the number that counts. Domestic 48 ft and 53 ft units are a different product: they are often 8 ft 6 in wide, and the builder sets the dimensions.

10 ft container dimensions

A 10 ft container is about 10 ft long, 8 ft wide, and 8 ft 6 in tall on the outside. Inside, plan on about 9 ft 3 in long, 7 ft 8 in wide, and 7 ft 10 in high, roughly 560 cubic feet. The door is often slightly smaller than a 20 ft door, about 7 ft 6 in wide by 7 ft 5 in high. The floor holds about four standard pallets.

It fits a tight site, a small tool store, or a project that does not need a 20 ft footprint. Ten-foot boxes vary more by manufacturer than 20 ft and 40 ft ISO units, and payload is not a simple fraction of a 20 ft rating. Read the plate on the unit you are buying or renting.

20 ft container dimensions

External size is 19 ft 10.5 in × 8 ft × 8 ft 6 in (6.06 × 2.44 × 2.59 m). Internal size is about 19 ft 4 in × 7 ft 8 in × 7 ft 10 in. The door opening is about 7 ft 8 in wide × 7 ft 6 in high. Usable volume is about 1,170 cubic feet (33.1 m³). A typical payload on many units is about 47,900 lb (21,700 kg). The floor holds about 10 standard pallets.

This is the usual box for dense cargo: steel, machinery, and palletized parts. The weight allowance often fills up before the floor does. A 20 ft high cube keeps the same length and width and adds a foot of height. Those measurements are in the high cube section below.

40 ft container dimensions

External size is 40 ft × 8 ft × 8 ft 6 in (12.19 × 2.44 × 2.59 m). Internal size is about 39 ft 5 in × 7 ft 8 in × 7 ft 10 in. The door opening matches a standard 20 ft: about 7 ft 8 in wide × 7 ft 6 in high. Usable volume is about 2,390 cubic feet (67.7 m³). A typical payload is about 59,040 lb (26,780 kg). The floor holds about 20 standard pallets.

The floor is about twice a 20 ft container. The legal payload is not. Light, bulky freight — furniture, insulation, packaged goods — is what the extra length is for. Dense freight often moves more weight in two 20 ft containers than in one 40 ft. The payload section below shows why.

Cargo doors are at one end. The first goods loaded sit at the far wall until everything in front of them comes out. If people need to reach the full length during the day, plan a personnel door or a second opening when you choose the size.

45 ft container dimensions

A 45 ft container in the US storage market is a high cube. External size is about 45 ft × 8 ft × 9 ft 6 in. Internal size is about 44 ft 4 in long, 7 ft 8 in wide, and 8 ft 10 in high. The door opening is about 7 ft 8 in × 8 ft 5 in. Usable volume is about 3,040 cubic feet, around 24 standard pallets.

The extra length helps when pallet count matters, especially retail and consumer freight. Not every chassis, port, or inland road accepts a 45 ft box without a restriction, so confirm the truck and the site before you commit. Payload is often in the same range as a 40 ft, because the longer shell weighs more. Use the CSC plate.

High cube container dimensions

A high cube has the same length and width as the standard container of that length. It is one foot taller: 9 ft 6 in outside instead of 8 ft 6 in, and about 8 ft 10 in inside instead of 7 ft 10 in. The door grows with the roof, to about 8 ft 5 in high, and stays about 7 ft 8 in wide.

	Standard	High cube
External height	8 ft 6 in (2.59 m)	9 ft 6 in (2.90 m)
Internal height	about 7 ft 10 in	about 8 ft 10 in
Door height	about 7 ft 6 in	about 8 ft 5 in
20 ft volume	about 1,170 cu ft	about 1,320 cu ft
40 ft volume	about 2,390 cu ft	about 2,700 cu ft

A 40 ft high cube holds roughly 13 percent more volume than a standard 40 ft. That extra foot is what makes it the practical default for bulky, light freight, and for offices or workshops: insulation, a ceiling, lights, and ductwork use the height a standard box does not have. A 20 ft high cube is the same change on the shorter footprint. Interior length stays about 19 ft 4 in, interior height is about 8 ft 10 in, the door is about 8 ft 5 in high, and volume is about 1,320 cubic feet. A 45 ft container is built as a high cube, so its height matches this column.

The extra foot can stop a delivery. Low bridges, tree cover, and overhead lines that clear an 8 ft 6 in box may not clear 9 ft 6 in. Check the route, not only the pad.

Door openings

Nominal length says almost nothing about what will pass through the doors. On a standard 20 ft or 40 ft container the opening is about 7 ft 8 in wide and 7 ft 5 in to 7 ft 6 in tall. That is narrower and shorter than the interior behind it. Door headers and corner castings take the rest. A high cube door is about the same width and about 8 ft 5 in tall. A 10 ft door is often about 7 ft 6 in × 7 ft 5 in.

A generator, a pallet, or a machine that fits the internal footprint can still jam in the doorway. Measure the cargo at its largest point, including the pallet, crate, wheels, and lifting hardware. Then compare that box to the door opening, not to the internal ceiling.

• Measure the piece the way it will be loaded, not the bare item.
• Check door width and door height against the widest and tallest point.
• Confirm the doors can swing clear of the wall, the rack, or the truck.
• Leave room for dunnage and straps. They take inches you do not get back.
• On a modified unit, measure again. A roll-up door, lining, or shelving changes the opening the base chart does not show.

Payload and weight limits

Dimensions say how much space the box has. They do not say how much weight the box, the truck, or the site can take. Every container is marked with three weights:

• Tare — the empty container.
• Payload — the load you may put inside.
• Maximum gross mass — tare plus payload. This is the rating on the CSC plate.

A 40 ft container has about twice the floor of a 20 ft and not twice the payload. Working figures for many dry boxes still in service are about 47,900 lb (21,700 kg) for a 20 ft, about 59,040 lb (26,780 kg) for a 40 ft, and about 58,080 lb (26,350 kg) for a 40 ft high cube. Two 20 ft containers, each with its own gross-mass allowance, often carry more legal weight than one 40 ft. Dense cargo — machinery, metal, bagged aggregate — is the case where that matters.

If the freight is heavier than about 15 to 20 pounds per cubic foot, run the weight before you pick the longer box. Light freight rarely hits the plate. A load can also be inside the plate rating and still be over a state axle limit once it is on a chassis. Check the road, not only the ISO number.

For a container that stays on site, watch point loads. A wood floor can be damaged by a machine, a pallet jack, or a stack of steel on a small footprint. Spread the load. If the container will move again, the plate is still the limit.

Which size to order

Use this chart for the measurements. Choosing between a 10 ft, 20 ft, and 40 ft for a jobsite, an office, or day-to-day access is a different question: aisle space, door type, and whether the truck can reach the pad. That decision is covered in what size shipping container you need.

Conexwest sells and rents these sizes, including high cube. Have the largest cargo dimension, the door opening you need, and the delivery path before you order. Browse shipping containers for sale.