📊 Barcode Check Digit Validator
📊 Barcode Check Digit Validator
Enter a barcode to validate it.
How it works
EAN/UPC/GTIN codes weight alternating digits 1 and 3 from the right, sum them, and the check digit is
whatever takes the total up to the next multiple of ten. ISBN-10 instead weights 10 down to 1 and uses
modulo 11, where the remainder 10 is written as X. A single mistyped digit always changes
the checksum, which is what catches scanning and keying errors.