Check Digit / Checksum

A Check Digit, also known as a Checksum character, is the number located on the far right side of a barcode. The purpose of a Check Digit is to verify the information of the barcode which has been entered correctly. The decoder of barcode scanner calculates the checksum by performing a series of mathematical operations on the digits preceding the Check Digit, and comparing the result of the calculation to the value of the Check Digit.
barcode check digit