How much payload does a container have?
A 20ft container takes around 28 tonnes of payload, a 40ft container around 26.6 tonnes. Surprisingly, the smaller 20ft often has the higher permitted payload — with heavy goods it is weight, not size, that is the real limit.
Max. payload at a glance
Payload is not a figure of its own, it is a difference: maximum gross weight minus the container's own weight (tare).
| Container | Max. gross | Tare (approx.) | Max. payload | Volume |
|---|---|---|---|---|
| 20′ Standard | 30,480 kg | 2,280 kg | 28,200 kg | ≈ 33 m³ |
| 20′ High Cube | 30,480 kg | 2,330 kg | 28,150 kg | ≈ 37 m³ |
| 40′ Standard | 30,480 kg | 3,880 kg | 26,600 kg | ≈ 68 m³ |
| 40′ High Cube | 30,480 kg | 3,900 kg | 26,580 kg | ≈ 76 m³ |
| 45′ High Cube | 32,500 kg | 4,900 kg | 27,600 kg | ≈ 86 m³ |
That also explains why the small container carries more: the permitted gross weight is the same for 20ft and 40ft (30,480 kg), but the 40-footer is around 1.6 tonnes more steel. Exactly that is missing from the cargo.
What counts is always the CSC plate on the container door — it carries the tare and max. gross of that specific container. The values above are common guide values and the same ones the 3D calculator works with.
The limit that bites first: the road
The container may take 28 tonnes — the truck bringing it to the terminal often may not. In Germany and most of the EU a semi-trailer combination is limited to 40 tonnes, and to 44 tonnes on the road leg of intermodal transport. The vehicle comes off that first:
| Item | 40 t combination | 44 t (intermodal) |
|---|---|---|
| Permitted gross combination weight | 40,000 kg | 44,000 kg |
| − tractor unit + chassis (typical) | 12,000 kg | 12,000 kg |
| − tare of a 40′ high cube | 3,900 kg | 3,900 kg |
| = possible on the road | 24,100 kg | 28,100 kg |
| Container permits | 26,580 kg | 26,580 kg |
Without the intermodal allowance the road is the tighter limit — around 24 instead of 26.6 tonnes. Load the container to its own limit and you have a full container that is not allowed to move. Vehicle and chassis weights vary by more than a tonne depending on specification; the figures above are a worked example, not a value for your combination.
VGM: the weight has to be declared before loading
Since 1 July 2016 the SOLAS convention (chapter VI, regulation 2) requires a Verified Gross Mass (VGM) for every sea container. No VGM, no loading. Two methods are permitted:
- Method 1: the packed container is weighed as a whole.
- Method 2: all individual items are added up — goods, packaging, pallets, dunnage and securing material, plus the container tare. The procedure has to be certified.
For method 2 the sum of the package weights is the starting point — exactly the figure the calculator reports. It is not yet a VGM: pallets, lashings and container tare come on top, and the responsibility for the declaration stays with the shipper.
Weight or volume — which runs out first?
Both limits apply at once. Which one bites is decided by the density of your cargo:
| Cargo | Density (rough) | Limit in a 40′ |
|---|---|---|
| Tiles, natural stone | > 1,000 kg/m³ | Weight, by a mile |
| Beverages, canned goods | 600–900 kg/m³ | Weight |
| Machine parts | 300–600 kg/m³ | Either way |
| Textiles, furniture, packaging | < 250 kg/m³ | Volume |
The threshold in a 40ft container is around 390 kg/m³ (26.6 t ÷ 68 m³). Above it the container is heavy before it is full — and then two 20-footers beat one 40-footer: together they carry 56.4 tonnes, the 40ft only 26.6.
The 3D calculator shows both in parallel and warns when the cargo entered exceeds the payload — even when there would still be space. With several containers it also levels the weight across them instead of filling the first to the brim and leaving the last half empty.
Frequent questions
How much does an empty container weigh?
A 20ft container weighs around 2.3 tonnes, a 40ft standard container around 3.8 and a 40′ high cube around 3.9 tonnes. The exact value is printed as "TARE" on the door.
What happens if a container is overloaded?
The carrier can refuse it, and on the road it means a fine and an immediate stop. Exceeding the permitted gross weight is not only the driver's liability — the shipper is on the hook too.
Can the payload be used in full?
From the container's point of view yes — but axle loads and weight distribution have to work out. Cargo concentrated at the front can exceed the fifth-wheel load even when the total weight is fine.
Enter the weight per package — the calculator shows live whether you stay under the payload.