3 ms·

There are card numbers that don't satisfy Luhn.

• drdaeman 2y ago
  I'm really curious now - which cards don't conform? I always thought it's basically an industry standard and no network issues cards that don't have a correct checksum.
  • ceejayoz 2y ago
    https://stackoverflow.com/questions/7863058/does-the-luhn-algorithm-work-for-all-mainstream-credit-cards-discover-visa-m https://stackoverflow.com/questions/7863058/does-the-luhn-al... has a list.
    • drdaeman 2y ago
      Wow, thank you. TIL!
• exikyut 2y ago
  TIL, although this isn't a field I need perfect knowledge of. I wonder if people with such cards have inexplicable problems with certain payment systems? Edit: just saw the sibling comment, was viewing an old copy of the page