Check Digit Calculator

Check your container number

Use the SCF Check Digit Calculator to determine if your container number is correct. A container number will display as incorrect if you have the wrong check digit (last number). Insert the container number in the form below and click on CHECK.

New and Improved

We have recently made changes to improve your ability to enter and copy a large volume of digits from within the tool

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.

You can use our calculator to work out what the check digit will be by adding the first 10 characters, or, if the check digit is valid.