SCF Online Containers

Specialists in shipping container sales, hire and design

Check Digit

What is a shipping container check digit?

All shipping containers used for rail & sea including specialised equipment must have a unique identification number. This number is calculated from:

The four letter prefix. The first three letters designate the owner, the fourth is always “U” identifying the unit as a container. e.g. SCFU – SCF Containers unit

The next 6 numbers. These numbers are decided by the owner according to their own numbering system. e.g. 205122

The last digit is called the check digit, this digit is usually outlined with a box.

The check digit is there so you can pick up any mistakes which might be caused by incorrectly writing down the container number, or incorrectly reading the container number. It does not matter who the owner of the container is or where the container is located, if you have a wrong check digit you have an invalid container number. Therefore it is likely that the container number does not exist!

Please feel free to use our check digit calculator, just put the container number in the form below and click on ‘CHECK’. You can use our calculator to work out what the check digit will be, or, if the check digit is valid.