20ft vs 40ft Container — Which Should You Book?
Most shippers default to 40ft without checking. Enter your cargo volume and weight — the answer might save you money.
Enter your cargo volume and weight above
Container Specifications at a Glance
Key differences between the three most-booked container types — all from the same ISO standard fleet.
Internal dimensions
5.90 × 2.35 × 2.39 m
Volume capacity
33.2 m³
Max payload
28,180 kg
Tare weight
2,200 kg
Max gross weight
30,480 kg
Door opening
2.34 × 2.28 m
Best for
Dense, heavy cargo. Steel, machinery, chemicals, beverages. Ideal when weight fills the box before volume does.
Internal dimensions
12.03 × 2.35 × 2.39 m
Volume capacity
67.7 m³
Max payload
26,680 kg
Tare weight
3,750 kg
Max gross weight
30,480 kg
Door opening
2.34 × 2.28 m
Best for
General cargo, mixed goods, light-to-medium density shipments. The global default — highest availability.
Internal dimensions
12.03 × 2.35 × 2.70 m
Volume capacity
76.3 m³
Max payload
26,500 kg
Tare weight
4,000 kg
Max gross weight
30,480 kg
Door opening
2.34 × 2.58 m
Best for
Tall cargo, lightweight bulky goods, furniture, mattresses. The extra 30 cm of height makes a significant difference for stacking.
Payload vs volume
The 20ft has a significantly higher payload than the 40ft (28,180 vs 26,680 kg) because it is shorter and weighs less (tare 2,200 vs 3,750 kg) — leaving more of the 30,480 kg gross limit available for cargo. For dense, heavy goods this matters.
When Each Container Makes Sense
The right choice depends on cargo density, not just volume. Here is when to use each option.
When your cargo is heavy or dense
- Cargo weight exceeds 14,000 kg — a 20ft lets you maximise payload before hitting the truck axle limit
- Dense goods: steel, machinery, liquids, ceramics — volume fills up after weight does
- You are shipping to a port where 40ft containers have a surcharge or lower availability
- Your cargo CBM is between 20–33 m³ and you want the most cost-efficient FCL option
When your cargo is voluminous or light
- Cargo CBM is between 30–65 m³ — a 40ft gives you room without paying for a second box
- Light goods: clothing, plastics, paper, electronics — you hit the volume limit long before the weight limit
- You are consolidating goods from multiple suppliers with different timing
- Rate difference between 20ft and 40ft is less than 60% — at that point the 40ft wins on cost per CBM
When height is a constraint
- Cargo height exceeds 2.20 m — the 40ft standard's 2.39 m internal height leaves little margin for pallets + cargo
- Furniture, mattresses, large machinery, or any goods that cannot be dismantled or laid flat
- CBM is between 68–76 m³ — only the HC offers enough volume
- Often only marginally more expensive than a 40ft standard — always check the rate before dismissing it
When your cargo is small
- Cargo is under 10–12 CBM — LCL is almost always cheaper at this volume
- You cannot fill at least 25–30% of a 20ft — you would be paying for mostly empty space
- Transit time flexibility is acceptable — LCL adds 3–7 days for consolidation and deconsolidation
- Note: LCL has higher handling risk and requires more documentation. For fragile or high-value goods, a half-empty FCL may be the safer choice
Booking Mistakes That Cost Money
These are the most common container selection errors shippers make — and how to avoid them.
Always defaulting to a 40ft
Many shippers book a 40ft out of habit, even when 15–20 CBM of heavy goods would sit perfectly in a 20ft at a fraction of the cost. Always calculate first.
Ignoring the payload difference
The 20ft has 1,500 kg more payload than a 40ft. For heavy cargo — steel, machinery, chemicals — this means you can legally load more per container in a 20ft.
Forgetting internal height
A 40ft standard has only 2.39 m internal height. Once you add a pallet (15 cm) and your cargo, you may find goods over 2.20 m won't fit without a High Cube.
Planning by volume alone
A container with 20 CBM of ceramic tiles is overweight before it is half full. Always check both CBM utilisation and weight utilisation — whichever hits 100% first is your binding constraint.
Using LCL for cargo over 15 CBM
Above 12–15 CBM, FCL often becomes competitive with LCL — especially when you factor in CFS handling fees, longer transit, and higher damage risk in LCL consolidation.
Not checking container availability
At some ports, 20ft or 40HC containers are scarce. Always confirm availability with your freight forwarder at origin before committing to a container type in your booking.