Sea freight Infocenter


Here you will find an overview of the most popular shipping containers and reefers, incl. dimensions, volumes and maximum load (standard values). Unlike air freight containers, shipping containers may be loaded by the clients themselves.

The dimensions, fittings and stackability of shipping containers are standardised by the International Maritime Organisation (IMO) and specified in the ISO Standard 668. The containers are generally 20 or 40 foot in length.

Shipping containers can be transported over land and water without any problems, since they are easy to fit to trains and HGVs. This eliminates the need to transfer individual consignments at the port or railway station.

Containers are assigned a special identifier to ensure ease of international identification. The first four capital letters indicate the owner, followed by a six-digit check number.

20ft general purpose container

Inside dimensions 5,9 x 2,3 x 2,4 m
Useable volume 33,2 m³
Door opening 2,3 x 2,2 m
Max payload (tons)* 28,2

40ft general purpose container

Inside dimensions 12 x 2,3 x 2,4 m
Useable volume 67,7 m³
Door opening 2,3 x 2,2 m
Max payload (tons)* 26,7

40ft high cube general purpose container

Inside dimensions 12,0 x 2,3 x 2,7 m
Useable volume 76,3 m³
Door opening 2,3 x 2,5 m
Max payload (tons)* 26,4

20ft flat rack

Inside dimensions 5,6 x 2,2 x 2,2 m
Useable volume 25 m³
Max payload (tons)* 37

40ft flat rack

Inside dimensions 11,6 x 2,2 x 2,2 m
Useable volume 52,7 m³
Max payload (tons)* 39,3

20ft open top container with detachable tarpaulin

Inside dimensions 5,3 x 2,2 x 2,2 m
Useable volume 32 m³
Max payload (tons)* 28,2

40ft open top container with detachable tarpaulin

Inside dimensions 12,0 x 2,3 x 2,3 m
Useable volume 65,5 m³
Max payload (tons)* 26,6

20ft reefer container

Inside dimensions 5,4 x 2,2 x 2,1 m
Useable volume 28,3 m³
Door opening 2,2 x 2,2 m
Max payload (tons)* 27,3

40ft high cube reefer container

Inside dimensions 11,5 x 2,2 x 2,2 m
Useable volume 60 m³
Door opening 2,5 x 2,2 m
Max payload (tons)* 27,7

Dangerous goods

There are exact regulations concerning dangerous goods which must be followed for sea freight transport. Did you actually know that common PR gifts, like filled gas lighters, matches, glues etc., can be dangerous goods? Moreover, there are often dangerous devices in the finished appliance - e.g. devices with batteries, gas cartridges etc.

If you are not the manufacturer yourself you should be well-informed about your goods. Since in the event of an accident (due to undeclared or falsely declared dangerous goods) the sender or the client is exclusively liable for the consequent damage.

All dangerous goods must be declared as such and be correspondingly packaged.
The stipulated dangerous goods signs must be enclosed.

Calculation table

When cooperating with foreign companies you might find measurements which are not common. The following table should help you to calculate these "exotic" values into the units commonly used.

Length measurement

1 inch 2,5400 cm
1 foot 0,3048 m
1 yard 0,9144 m
1 mile 1,6093 km
1 cm 0,3937 inch
1 m 3,2808 foot
1 m 1,0936 yard
1 km 0,6214 miles

Space measurement

1 inch³ 16,387 cm³
1 foot³ 0,0283 m³
1 cm³ 0,0610 inch³
1 m³ 35,3156 foot³
1 yard³ 0,7646 m³
1 m³ 1,3079 yard³

Surface measurement

1 inch² 6,452 cm²
1 foot² 0,0929 m²
1 cm² 0,1550 inch²
1 m² 10,7639 foot²
1 yard² 0,8361 m²
1 m² 1,1960 yard²

Weight measurement

1 Pound 0,4536 kg
1 Ounce 28,3495 g
1 kg 2,2046 Pound
1 g 0,0353 Ounzes

New SOLAS regulation for Verified Gross Mass

The International Maritime Organization (IMO) has made an amendment to the Safety of Life at Sea Convention (SOLAS): it requires that every packed container be assigned a verified gross weight.
As of July 1st, 2016 it is the shippers responsibility to determine the container weight and to submit the Verified Gross Mass (VGM) to the ocean carriers, before loading the container onto a vessel for export. Without submitting the VGM, the container will be rejected from the port authorities and will not be loaded onto the vessel.
There are two accepted methods of calculating the verified gross mass of a container; which is weighing the stuffed container (Option 1) or weighing all cargo, adding dunnage and the tare weight of the container, which can be found at the door of the container (Option 2).  
For all FCL containers the Consignor is obliged to submit the VGM declaration to us by filling in the VGM declaration sheet (see attachment). As some ports do have a “no VGM, no gate-in” policy, the document needs to be submitted to your respective contact person at Röhlig latest at time of packing the container, prior to leaving the premise. To ensure an immediate processing, the declaration should be send via e-mail. A hard copy of the declaration is to be handed over to the driver of the trucking company in addition.
For your further reference, kindly see below timeframe for the VGM procedure for FCL container, in cases when you are able to verify the cargo weight yourself (you have a scale on site).

In case you are unable to determine correct the cargo weights we offer weighing services at cost.  If weighing services are arranged by Röhlig, the weight will be declared to the carrier based on the scale weight provided by the Röhlig agent weighing the container.  See below timeframe as reference. Please contact your Röhlig contact person for more detailed information and possible extra-incurred costs.

For all LCL shipments, the NVOCC is responsible for obtaining the VGM, by weighing the packed container. Therefore no VGM declaration is needed, only the actual weight and volume of the cargo.

For any assistance or further information, do not hesitate to contact your local representative at any time.