GS1 Modulo 10
The GS1 Modulo 10 algorithm is the universal check digit method for retail and supply chain barcodes, including EAN-13, UPC-A, EAN-8, ITF-14, SSCC, and GTIN-14. It uses alternating weights of 1 and 3 applied to the data digits, with the check digit chosen so that the total weighted sum is a multiple of 10.