It’s no particular secret that almost every credit card there may be an outlier lying out there somewhere, I suppose has been designed to pass the Luhn test, a relatively simple check-digit routine. It’s no particular trick to come up with a number that appears to pass muster, even if it doesn’t correspond to an actual account, and unsurprisingly, there’s an app for that:
GetCreditCardNumbers comes to your rescue by giving out fake, “real” credit card numbers that can be used when you need one to get a trial underway, you know, like the ones available at Netflix, Hulu and the likes. Well, we say “real” because obviously enough, they aren’t actual real life credit card numbers but merely a collection of digits that have all the right formatting needed to fool a computer into thinking that they make up a proper card number. That is, the numbers have the required issuer identification number and the like, so they’re more than just a collection of random numbers thrown onto a website. In fact, if you need a large number of real-fake credit cards to use, the website will even let you download 100s in a fancy XML, JSON or CSV file.
They certainly look plausible enough. If a merchant actually runs them, though well, I’ve seen this before, and I recognize most of the error codes on sight.