A 20 ft container is 20 ft long, 8 ft wide and 8 ft 6 in tall outside, with about 149 sq ft of floor and 1,172 cu ft inside. A 40 ft is twice the length: about 305 sq ft and 2,391 cu ft. A 40 ft high cube adds a foot of height for 2,695 cu ft.12
Sizes at a glance
| Spec | 20 ft standard | 40 ft standard | 40 ft high cube |
|---|---|---|---|
| Outside (L x W x H) | 20 ft x 8 ft x 8 ft 6 in | 40 ft x 8 ft x 8 ft 6 in | 40 ft x 8 ft x 9 ft 6 in |
| Inside length | 19 ft 4¼ in | 39 ft 5⅝ in | 39 ft 5⅝ in |
| Inside width | 7 ft 8⅝ in | 7 ft 8⅝ in | 7 ft 8½ in |
| Inside height | 7 ft 10¼ in | 7 ft 10¼ in | 8 ft 10¼ in |
| Door opening (W x H) | 7 ft 8⅛ in x 7 ft 6¼ in | 7 ft 8⅛ in x 7 ft 6¼ in | 7 ft 8⅛ in x 8 ft 6¼ in |
| Floor space | About 149 sq ft | About 305 sq ft | About 304 sq ft |
| Capacity | 1,172 cu ft (about 43 cu yd) | 2,391 cu ft (about 89 cu yd) | 2,695 cu ft (about 100 cu yd) |
| Empty (tare) weight | About 5,070 lb | About 8,160 lb | About 8,490 lb |
| Through our provider network | Yes | Yes | Specs only |
Measure against the door. Doors are slightly narrower and lower than the inside: about half an inch in width and 4 inches in height. Check your load against the door opening, not the interior.
Where the numbers come from. Outside sizes follow ISO 668. Inside sizes, doors, capacity and tare come from one ocean carrier's fleet spec. Most storage units are retired shipping containers, so a box can differ by a fraction of an inch and tare varies by build. For a tight fit, ask for the spec of the actual unit. Floor space and cubic yards are our math from those figures.12
Choosing a length
For a single job site or a business that needs overflow storage. It fits where a 40 won't, and it's the size our provider network places most.
Roughly twice the floor in one footprint, for long jobs, warehouse overflow or sites with lots of material. Supply is thinner in many markets, so confirm before you plan around one.
Worth it for racking or rolled goods. It's shown here for reference; we don't list it as something we place.
Conex vs shipping container
Conex comes from the US Army. In 1948 its Transportation Corps adopted a steel box it called the Transporter: 8 ft 6 in long, 6 ft 3 in wide and 6 ft 10 in high, rated for 9,000 lb, with double doors at one end. In late 1952 the Container Express, or CONEX, replaced it, and on the run from a US depot to Japan, delivery time fell from about 55 days to 27.3
What you rent today is the commercial box that came after, built to the ISO 668 sizes in the table above.1 People in the US still call it a conex, and when a customer asks us for one we treat the two words as the same container. The original Army CONEX was smaller than a modern 20.
A converted conex office is the same shell with a finished room inside, covered below.
Detritus delivery records, October 26, 2024 through October 26, 2026, canceled orders excluded.
Offices and combos
Our provider network also places converted containers: a 20 ft office, and 20 ft and 40 ft office-and-storage combos with an office at one end and storage behind a partition.
They need power and usually steps or a ramp. Finish, windows, HVAC and partition placement vary, so the inside dimensions above don't apply. The floor plan comes with the quote.
Site needs
Plain storage needs no power or utility hookup. It needs ground, an approach and a decision about the doors.
Pricing depends on market, length, term and delivery distance, so every site gets its own quote.
Send the address, the length you want, how long you need it and which way the doors should face. We come back with a container and a price from the provider network.
Questions
7 ft 8⅛ in wide on all three. It's 7 ft 6¼ in tall on a standard container and 8 ft 6¼ in on a high cube.2
About 5,070 lb. A 40 is about 8,160 lb and a 40 high cube about 8,490 lb.2
About 149 sq ft of floor inside. A 40 is about 305.
Yes. CONEX was the US Army's name for its steel shipping boxes from 1952, and in the US it stuck as a name for any shipping container. Sizes are the same.3
Rarely. We delivered fewer than 10 in the last two years, and dimensions vary by builder, so ask us.
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