The 20ft and the 40ft are the two highest-volume shipping container sizes on the planet, and for most buyers the whole decision comes down to those two boxes. This guide puts them side by side on the four things that actually decide it: capacity, cost per cubic foot, the space your site needs to receive one, and what you plan to do with it afterwards.
The short version, if you want it now: a 40ft container gives you roughly double the volume for well under double the price, so it wins on value — but only if your site can take the truck. A 20ft fits where a 40ft simply will not, and that is not a compromise so much as a different problem being solved.
20ft vs 40ft: The Numbers Side by Side
| Specification | 20ft standard | 40ft standard | 40ft high cube |
|---|---|---|---|
| External L × W × H | 20' × 8' × 8'6" | 40' × 8' × 8'6" | 40' × 8' × 9'6" |
| Internal L × W × H | 19'4" × 7'8" × 7'10" | 39'5" × 7'8" × 7'10" | 39'5" × 7'8" × 8'10" |
| Door opening W × H | 7'8" × 7'6" | 7'8" × 7'6" | 7'8" × 8'6" |
| Internal capacity | ~1,170 cu ft | ~2,390 cu ft | ~2,700 cu ft |
| Floor area | ~148 sq ft | ~302 sq ft | ~302 sq ft |
| Tare weight | ~4,850 lb | ~8,200 lb | ~8,750 lb |
| Ground footprint | ~160 sq ft | ~320 sq ft | ~320 sq ft |
Notice that the 40ft is not exactly twice the 20ft internally — it is a little over twice on volume, because the corner posts and end walls are a fixed overhead you only pay once. That is the structural reason the cost per cubic foot falls as you go up in length.
Cost per Cubic Foot: Where the 40ft Wins
Take two cargo-worthy units from our own catalog and divide the price by the capacity. A cargo-worthy 20ft standard at roughly $1,950 works out near $1.67 per cubic foot. A cargo-worthy 40ft standard at roughly $2,150 works out near $0.90 per cubic foot — close to half the cost for the same stored volume. A 40ft high cube at about $2,250 is cheaper still per cubic foot, because you get another 310 cubic feet for a small premium.
Add the flat $500 delivery to each and the gap narrows a little but does not close. Delivery is the same $500 whether you are taking a 20ft or a 40ft, which pushes the value further towards the bigger box: you pay the freight once either way.
| Unit | Catalog price | Capacity | Cost per cu ft | Plus $500 delivery |
|---|---|---|---|---|
| 20ft cargo-worthy | ~$1,950 | ~1,170 cu ft | ~$1.67 | ~$2.09 |
| 40ft cargo-worthy | ~$2,150 | ~2,390 cu ft | ~$0.90 | ~$1.11 |
| 40ft HC cargo-worthy | ~$2,250 | ~2,700 cu ft | ~$0.83 | ~$1.02 |
Two 20ft containers are almost always more expensive than one 40ft for the same total volume — you pay two delivery fees, two sets of doors and two sets of corner posts. Buy two 20ft units only when you genuinely need them in two places, or when you want to separate contents.
Delivery Access: The Constraint That Overrules Everything
This is the factor that most often makes the decision for people, and it is worth checking before you fall in love with a size. A tilt-bed truck does not lift a container down; it tilts the bed and slides the box off backwards while creeping forward. That means it needs a straight, firm run considerably longer than the container itself.
| Requirement | 20ft delivery | 40ft delivery |
|---|---|---|
| Straight-line clearance | Container length plus roughly 40 ft | Container length plus roughly 40 ft |
| Practical total run | ~60 ft | ~80 ft |
| Width of path | ~12 ft clear | ~12 ft clear |
| Overhead clearance | ~15 ft | ~15 ft |
| Turning and maneuvering | Easier — shorter rig, tighter radius | Needs a wider approach and more swing room |
| Ground bearing | Firm; soft ground bogs a loaded truck | Firm; heavier load, less tolerance |
Suburban lots, alley access, tree-lined driveways and anything with a tight corner tend to rule out a 40ft. If you are unsure, measure the straight run from where the truck will enter to where the doors will end up, and check for wires and branches along the whole path. The delivery walkthrough covers what to look for in more detail.
When to Choose a 20ft
- Tight or urban sites. A 20ft occupies about the footprint of a single parking space and is far easier to position.
- Household and small-business storage. 1,170 cubic feet swallows the contents of a substantial garage or a two-to-three bedroom home's worth of furniture.
- Lower total outlay. When budget rather than value-per-foot is the constraint.
- Future relocation. A 20ft is cheaper and easier to move again later.
- Small conversions. Bars, kiosks, guard booths and single-room offices work well at 20ft.
Our 20ft container range spans storage-class used units through one-trip stock; a new 20ft x 8ft unit is a common choice where appearance matters on a domestic property.
When to Choose a 40ft
- Bulk storage. Pallets, machinery, seasonal inventory, vehicles, farm equipment.
- Best cost per cubic foot. The strongest value in the whole size range.
- Conversion projects with rooms. 302 square feet gives you room for a partition and still leaves usable space either side.
- Anything long. Timber, pipe, ladders, boats and kayaks that will not fit diagonally in a 20ft.
- Racking and shelving. A long straight run of racking is much more efficient than two short ones.
See the 40ft container listings for what is available, including a cargo-worthy 40ft high cube if you want the extra headroom.
Don't Forget the Third Option: High Cube
Height is a separate decision from length, and it is the one people regret most often. A high cube container stands 9'6" instead of 8'6", giving about 8'10" of interior height instead of 7'10". For pure storage that extra foot buys another shelf. For a conversion it is close to essential, because once you have added a raised floor, insulation on the ceiling and a light fitting, a standard-height box gets low fast.
High cube is standard on 45ft and 53ft units and optional on 20ft and 40ft. Full figures for every size are in the container specifications reference.
Capacity in Plain Terms
| What you're storing | 20ft holds roughly | 40ft holds roughly |
|---|---|---|
| Standard 40" × 48" pallets, floor-loaded | 10–11 | 20–21 |
| Household contents | A 2–3 bedroom home | A 4–5 bedroom home |
| Cars (unmodified box, no lift) | 1 | 2 end to end |
| Standard shelving runs (both walls) | ~19 linear ft each side | ~39 linear ft each side |
These are working approximations rather than fixed figures — how much fits depends entirely on how well it stacks. Anything that cannot be stacked wastes vertical space fast, which is another argument for high cube.
Making the Call
Work through it in this order and the answer usually appears on its own:
- Measure the site first. If you cannot get 80 feet of straight, firm, 12-foot-wide access, the 40ft is out and the decision is made.
- Estimate the volume you need, then add a third. Almost nobody wishes they had bought smaller.
- Decide on height. Conversion or tall goods? Go high cube.
- Pick the grade to fit the budget. Buying down the grade is nearly always better than buying down the size.
Still weighing it up? Call our team and describe the site and what is going in it — that conversation takes five minutes and settles most of these decisions.
Frequently Asked Questions
Is a 40ft container twice the price of a 20ft?
No. In our catalog a cargo-worthy 40ft standard is roughly $2,150 against about $1,950 for the equivalent 20ft, despite holding more than twice the volume. The end walls, corner castings and door gear are a fixed cost you pay once, so cost per cubic foot falls sharply with length.
How much room do I need for a 40ft container delivery?
Allow the container's length plus roughly 40 feet of straight, firm clearance so the tilt-bed truck can slide the unit off — about 80 feet in total for a 40ft box. You also need around 12 feet of clear width and about 15 feet of overhead clearance along the whole approach.
Can I get two 20ft containers instead of one 40ft?
You can, but it usually costs more for the same total volume: two boxes means two sets of corner posts and door gear, and two delivery charges rather than one. Two 20ft units make sense when you need storage in two locations, or when you want contents physically separated.
Does a 40ft container weigh too much for a residential driveway?
An empty 40ft standard has a tare weight of roughly 8,200 lb, and the loaded delivery truck weighs far more than the container itself. Concrete driveways, asphalt and soft ground can all be marked or cracked by the rig, so plan the approach route as carefully as the final placement.
Which size is better for a container conversion?
A 40ft high cube, in most cases. The extra length gives room for a partitioned layout and the extra foot of height absorbs the raised floor, ceiling insulation and lighting that a conversion adds. Start from one-trip stock if the finish matters, since you only cut and paint once.