A standard 40-Foot shipping container measures 40 feet long, 8 feet wide, and 8 feet 6 inches tall on the outside. Inside, the usable floor works out to roughly 305 square feet, with a storage volume of about 2,350 cubic feet. A 40-foot High Cube version keeps the same length and width but adds a full foot of interior height, pushing capacity to roughly 2,694 cubic feet. If you need one number to remember: a 40-foot container gives you about the footprint of a two-car garage in a single steel box.
How Big Is a 40-Foot Shipping Container?
40-Foot describes the exterior length, not the space you actually get to use. Steel walls, corner castings, and the door frame all take up room, so the interior is always a little smaller than the label suggests. Understanding that gap between nominal size and usable size is the whole point of this reference.
Aztec Container has supplied 40-foot ISO steel containers since 1969, and the dimensions below reflect the standard ISO specification the industry builds to. These are the numbers to plan around before you commit to a unit.
40-Foot Container Dimensions (Standard ISO)
| Measurement | Dimension |
| Exterior Length | 40′ 0″ |
| Exterior Width | 8′ 0″ |
| Exterior Height | 8′ 6″ |
| Interior Width | 7′ 8.5″ |
| Interior Height | 7′ 10 3/16″ |
| Door Opening Width | 7′ 8 1/8″ |
| Door Opening Height | 7′ 5 1/2″ |
How Many Square Feet Are in a 40-Foot Container?
A standard 40-foot container delivers approximately 305 square feet of interior floor space. That figure comes from an interior width of about 7 feet 8.5 inches multiplied by the usable interior length of roughly 39 feet 5 inches — the steel frame trims a few inches off each end.
To put 305 square feet in perspective:
- About the size of a standard two-car garage, which typically runs 300–400 square feet.
- Roughly a small studio apartment’s footprint, minus the finishing.
- Enough floor for around 8 to 10 standard pallets placed in a single layer.
Square footage tells you how much floor you have. But because containers are tall, the more useful measure for most storage is cubic capacity — covered next.
40-Foot Container Storage Capacity (Cubic Feet)
A standard 40-foot container holds approximately 2,350 cubic feet of volume. When you stack and organize vertically, that’s a substantial amount of usable space:
- The contents of a typical three- to four-bedroom home, with room to spare.
- Roughly double what a 20-foot container holds, for far less than double the footprint.
- Enough for large inventory runs, equipment, seasonal stock, or fleet parts kept in one consolidated place.
Rule of thumb: think in cubic feet, not square feet, when you’re storing boxed or stackable goods. The vertical space is where a 40-foot container earns its keep.
Standard vs. High Cube: The One-Foot Difference That Matters
A 40-foot High Cube container shares the same length and width as the standard model but stands one foot taller — 9′ 6″ exterior height instead of 8′ 6″. That extra foot changes the math more than you’d expect:
| Feature | Standard 40′ | High Cube 40′ |
| Exterior Height | 8′ 6″ | 9′ 6″ |
| Interior Height (approx.) | 7′ 10″ | 8′ 10″ |
| Approx. Volume | ~2,350 cu ft | ~2,694 cu ft |
That single foot adds roughly 340 cubic feet of capacity. High Cube units are the go-to choice when you’re stacking tall, storing oversized equipment, or building out an office or specialty interior that needs headroom.
What Can You Actually Fit in a 40-Foot Container?
Because each section here should stand on its own, here’s a self-contained snapshot of real-world capacity. A single 40-foot container can typically hold:
- The furnishings and boxes of a 3–4 bedroom household.
- Two vehicles in a dedicated car-storage configuration.
- 8–10 pallets on the floor, or far more when stacked.
- A full small business inventory, workshop, or archive.
The right configuration matters as much as the size. Aztec Container offers 40-foot units as office containers, cargo-door and roll-up-door models (with one to four roll-up doors), full side-open designs, car storage, refrigerated, and insulated builds — so the same 305-square-foot footprint can be tuned to the job.
Choosing the Right 40-Foot Container
Aztec Container has built and supplied durable steel containers since 1969 from its Vista, California headquarters, with sales available nationwide and rentals available in California. As an NPSA member, the company stocks a full range of 40-foot configurations — standard, High Cube, office, refrigerated, insulated, and custom door layouts.
If you’re weighing a 40-foot unit against a 20-foot unit or need help matching a configuration to your space, the team can walk you through the numbers. Call 1-800-399-2126 for a quick quote and current stock.
Frequently Asked Questions (FAQs)
How big is a 40-Foot shipping container?
On the outside, it’s 40 feet long, 8 feet wide, and 8 feet 6 inches tall. Inside, you get about 305 square feet of floor and roughly 2,350 cubic feet of storage space — think of it as a two-car garage sealed into one steel box.
How many square feet is a 40-Foot shipping container?
About 305 square feet of usable interior floor. The exterior length is a full 40 feet, but the steel frame trims the interior down to roughly 39 feet 5 inches long, which is where that square-footage figure comes from.
What’s the interior height of a 40-Foot shipping container?
A standard 40-foot container has an interior height of about 7 feet 10 inches. If you need more headroom, the High Cube version gives you close to 8 feet 10 inches — a full foot taller inside.
How much can a 40-Foot shipping container hold?
Roughly 2,350 cubic feet, which is enough for the contents of a three- to four-bedroom home, a full small-business inventory, or 8 to 10 pallets on the floor with plenty of room to stack higher.
What’s the difference between a standard and a High Cube 40-foot container?
Same length, same width — the High Cube is simply one foot taller. That extra foot adds around 340 cubic feet of capacity, which makes a real difference if you’re stacking tall or need extra headroom for equipment or a built-out interior.
Will a 40-foot container fit two cars?
Yes. In a dedicated car-storage configuration, a 40-foot container comfortably holds two vehicles, which is why it’s a popular choice for collectors and anyone short on garage space.
How wide are the doors on a 40-Foot container?
The door opening is about 7 feet 8 inches wide and 7 feet 5 inches tall. That opening is the real limit on what you can load — if an item clears the doors, it will fit inside.
Is a 40-foot container twice the size of a 20-Foot container?
In floor length and volume, essentially yes — a 40-foot container roughly doubles the capacity of a 20-foot unit while taking up only twice the length and none of the extra width, which often makes it the better value per cubic foot.
How much space do I need to place a 40-Foot container?
Plan around the exterior footprint: 40 feet long by 8 feet wide, standing 8 feet 6 inches tall (or 9 feet 6 inches for a High Cube). It’s smart to allow clearance around the unit so the doors can open fully and you have working room.
What can I use a 40-Foot container for?
Plenty — bulk storage, vehicle storage, on-site offices, refrigerated or insulated builds, and fully custom configurations. Aztec Container offers 40-foot units in office, cargo-door, multi-roll-up-door, full-side-open, car-storage, refrigerated, and insulated versions, so the same footprint can be adapted to almost any use.