What Is the Luhn Algorithm? The Math Behind Credit Card Transactions
4 speckx 3 8/19/2025, 2:25:55 PM scientificamerican.com ↗
Comments (3)
bediger4000 · 4h ago
Fun Luhn fact: you can transpose any two odd or even indexed digits except the final check digit in a credit card number, and still get a card number that passes a Luhn checksum. You can use this to give cybercriminal scammers card numbers that probably aren't connected to any actual account.
cratermoon · 5h ago
... Did the author post his actual credit card number in that article?
resoluteteeth · 32m ago
> The number crunching culminates in 75, which is not a multiple of 10. So this cannot be my real credit card number; I must have mistyped it.