Worked example
The test sequence 590123412345 produces 5901234123457; changing the last digit to 8 fails validation instead of silently drawing a wrong symbol.
Before you print
EAN-13 is an image format for a GTIN-13. A valid check digit does not establish ownership of the GTIN or licensing from GS1.
Barcode artwork is not proof of an assigned GS1 number. A free barcode image and a GS1-issued GTIN are different things.