Dimensions and weight
maximum gross weight
Maximum gross weight is the most a container may weigh when loaded, including its own tare weight and the cargo. In ISO 668, ratings include the gross mass of the container. Carrier listings often show 30,480 kg for 20-foot and 40-foot dry containers.
Why it matters
This rating is a hard limit on the container. Cargo plus container weight must stay at or below it. A carrier lists some high cube and 45-foot units with a 32,500 kg option. Always use the plate or spec for the exact unit. The container rating is not the same as a road limit. A truck, trailer, bridge or state law may set a lower limit for the full load. A common mistake is to treat the container rating as the safe weight to haul. Check the CSC plate, the unit data and the legal weight for your route before you load or lift.
Read: Container delivery equipment: Tilt-bed, roll-off, side-loader, and crane trucks
Definition source: iso.org
Related terms
payload
Payload is the weight of cargo a container can carry. It equals the maximum gross weight minus the container's own empty (tare) weight. Carrier specs list payload next to tare weight for each container size and type, so buyers can compare them side by side.
tare weight
Tare weight is the weight of an empty container or vehicle. Subtract it from the gross weight to find the weight of the goods inside. On a shipping container, it is not set by the ISO standards. It depends on how the container was built.
GVWR
GVWR is gross vehicle weight rating. It is the maximum loaded weight of a single motor vehicle, as set by the manufacturer. It includes the vehicle, fuel, driver, cargo and equipment. It is printed on the vehicle's certification label and set by the maker.
GCWR
GCWR is gross combination weight rating. It is the greater of the manufacturer's value for the power unit or the sum of the GVWRs of the power unit and towed units. It is used for tractor-trailers and trucks that tow.
CSC plate
A CSC plate is a metal safety approval plate fixed to a freight container under the International Convention for Safe Containers. It shows that the container was approved for international transport and carries the technical data and examination information for that container. The plate is usually fixed to a container door.
ISO 668
ISO 668 is the international standard that classifies series 1 freight containers by their external dimensions. It sets the matching ratings, which include maximum gross mass, and gives minimum internal and door opening sizes for some container types. It covers containers meant for intercontinental traffic.
For the industry
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