The most common container types are the 20' and 40' standard (dry), the 40' high cube, the reefer (refrigerated), open top, flat rack and tank container. A 20' standard container measures approximately 5.90 × 2.35 × 2.39 metres inside, with a volume of 33 m³. In a 40' high cube, the internal height rises to 2.70 metres and the volume to about 76 m³.
Who sets container dimensions?
The external dimensions and maximum gross weights of international containers are defined by the ISO 668 standard, and the internal dimensions by type in the ISO 1496 series. The external width of all standard containers is 2.438 metres (8 ft). Standard height is 2.591 metres (8'6"), and high cube height is 2.896 metres (9'6"). Most containers on the market were built and marked with a maximum gross weight of 30,480 kg; although a 2016 amendment allows ratings up to 36,000 kg, the decisive value is the one on the CSC safety approval plate on the container door.
Main types and approximate dimensions
| Type | Internal dimensions (L × W × H) | Door opening (W × H) | Volume | Approx. maximum payload |
|---|---|---|---|---|
| 20' standard (DC) | 5.90 × 2.35 × 2.39 m | 2.34 × 2.29 m | 33 m³ | 28,000 kg |
| 40' standard (DC) | 12.03 × 2.35 × 2.39 m | 2.34 × 2.29 m | 67 m³ | 26,500–28,800 kg |
| 40' high cube (HC) | 12.03 × 2.35 × 2.70 m | 2.34 × 2.59 m | 76 m³ | 26,500–28,600 kg |
| 20' reefer | 5.45 × 2.29 × 2.26 m | 2.29 × 2.26 m | 28 m³ | 27,000 kg |
| 40' reefer HC | 11.58 × 2.29 × 2.55 m | 2.29 × 2.57 m | 67 m³ | 29,000 kg |
| Open top | Similar to dry, open roof | Door header can be swung open | 32 / 66 m³ | 28,000 / 26,500 kg |
| Flat rack | No side walls or roof | Not applicable | Not applicable | 20': ~30,000 kg, 40': ~40,000 kg |
| ISO tank | Tank within a 20' frame | Not applicable | Typically 21,000–26,000 litres | Depends on product density |
The values are indicative; they differ by a few centimetres and a few hundred kilograms depending on the shipping line, year of manufacture and container series. The carrier's current technical table should be requested before booking.
Which container for which cargo?
- Standard dry: General cargo such as cartons, pallets and bags. The 20' is advantageous for dense, heavy cargo, the 40' for voluminous cargo.
- High cube: Light but bulky products such as furniture, textiles and insulation materials; for details, see the entry high cube container.
- Reefer: Food, pharmaceuticals and chemicals that require temperature control, generally between −30 °C and +30 °C. The operating principle is explained in the entry how a reefer container works.
- Open top: Long and tall parts that do not fit through the door or must be loaded from above by crane; conditions of use are in the entry open top container.
- Flat rack: Machinery, cable drums and construction equipment whose width or height exceeds container dimensions; securing and clearance checks are explained under flat rack container.
- Tank: Liquid chemicals, food-grade oils and dangerous liquids.
What should you watch out for when loading?
The weight a container can carry and the weight that can be carried on the road are not the same. In Turkey, Article 128 of the Highway Traffic Regulation (Karayolları Trafik Yönetmeliği) sets the maximum laden weight of semi-trailer combinations carrying ISO containers (three-axle tractor and two- or three-axle chassis) at 44 tonnes. Once the tare weights of the tractor, chassis and container are deducted, the payload that can be carried on the road is around 26–27 tonnes; this is below the technical capacity of a 40' container. For heavy cargo, choosing a 20' container and distributing the load evenly across the floor therefore becomes important.
Under SOLAS, the verified gross mass (VGM) of every packed container to be loaded onto a ship is the shipper's responsibility. Cargo should be blocked and lashed so that no void space remains inside the container.
How does Voltim Global support you?
For container transport requests, Voltim Global recommends the container type according to the dimensions and weight of the cargo, and also factors the road weight limit between the port and the project site into the planning.