What Is the Luhn Algorithm? The Math Behind Credit Card Transactions

Comments (2)

bediger4000 · 2h 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 · 2h ago

... Did the author post his actual credit card number in that article?

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What Is the Luhn Algorithm? The Math Behind Credit Card Transactions

Comments (2)