How do credit card companies not run out of numbers?

Question

How do credit card companies not run out of numbers?

In: 0

Answer 1

There’s four groupings of four digits – that’s 9,999,999,999,999,999 possible unique credit card numbers. That’s 91,743 credit cards for every man, woman, and child that has ever lived…in the entire history of human beings.

Even if you factor in that Visa card numbers start with 4, Mastercard starts with 2 or 5, and American Express starts with 3….that’s still a shit-ton of possible numbers for every issuer.

And beyond that if you factor in that the issuing banks have unique numbers for the first 4 to 6 numbers, that still leaves a very high number of cards for the possible number of people that could have one.