Container Check Digit Calculator

Enter BIC Code:
U for all freight containers, J for detachable freight container-related equipment, Z for trailers and chassis.
Enter the first six digits of the starting serial number.
Enter the first six digits of the ending serial number.

You have the possibility to calculate 25 check digits at once if the serial number are sequential

What is a container check digit?

The container check digit provides a means of validating the transmission accuracy of the owner/operator code and serial number. This allows operators, terminals, depots and other parties in the supply chain to automatically validate container numbers and easily identify incorrect container numbers introduced through a data-entry error or an erroneous OCR (optical character recognition) reading.

How is a check digit calculated?

As the check digit is calculated using an algorithm that takes into account both the BIC code and serial number, it is imperative that the check digit be modified when containers are re-marked with a different BIC code.

Shipping Container Identification Number

The letters and numerals of the owner code, equipment category identifier, serial number and check digit shall be not less than 100 mm (4 in) high. All characters shall be of proportionate width and thickness, they shall be durable and in a colour contrasting with that of the container. The identification system provides uniform international identification of containers, in documentation and in communication associated with the movement of containers from door to door. It consists of:

  • The owner prefix (BIC code): three capital letters of the Latin alphabet to indicate the owner or principal operator of the container,
  • The equipment category identifier: one capital letter as follows:
    • U for all freight containers,
    • J for detachable freight container-related equipment,
    • Z for trailers and chassis,
  • The serial number: six Arabic numerals, left at owner‘s or operator‘s option,
  • The check digit: one Arabic numeral providing a means of validating the recording and transmission accuracies of the owner code and serial number.

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Bureau International des Containers et du Transport Intermodal

41, Rue Réaumur, 75003 PARIS, FRANCE
Tel: +33 147 660 390 | Fax: +33 147 660 891

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