How the calculation works
Starting with the last digit of the number’s body, multiply alternating digits by 3 and 1. Add the results. The check digit is the amount needed to reach the next multiple of ten, or zero when the sum is already a multiple of ten.
For EAN-13 body 590123412345, the weighted sum is 83, so the check digit is 7 and the complete number is 5901234123457.
This follows the method used by the GS1 check digit calculator. To check identifier ownership, use Verified by GS1.
Then draw the symbol in the barcode generator. If you are choosing between formats, read QR codes vs barcodes on Game Funtastic, our sister project.