We just completed a feature that checks for missing check digits required for making a valid UPC or EAN. To learn more about what a check digit is and how/when our system generates them, please see below.
What is a Check Digit?
A check digit is a form of redundancy check used for error detection on identification numbers. It consists of a single digit computed by an algorithm from the other digits in the sequence input.
The final digit of a Universal Product Code (UPC) or European Article Number (EAN) is a check digit computed by a short algorithm using the individual numbers in the value.
When and How does our System Recognize and Generate a Check Digit?
A valid Amazon UPC has 12 digits total and a valid Amazon EAN has 13 digits total. Our system will recognize if a UPC or EAN is short of these numbers. If so, we’ll first search the UPC/EAN with a leading 0 to make up the 12th or 13th digit (depending on if it’s a UPC or EAN). If we don’t return a result for the UPC/EAN with a leading 0, we flag this number and leave it labeled in the system as ‘New Inventory’. Once your full conversion is complete, our system will notify you that we found possible records that may need a check digit generated. We then generate the check digit for each flagged record and do a search to fully complete your conversion.
Important: This feature only activates for numbers that have less than their required amount. If you get a file of UPCs from your vendor with only 11 digits, don’t generate the leading 0 before you import to our system. Instead, import the file with the 11 digits and our system will do the work for you.