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0 pointspudquick13y ago0 comments

Did you mean verify that an account is associated with the credit card?

Or just verify that the credit card number is potentially a legitimate one?

Because if it's the latter, that's just the Luhn algorithm (http://en.wikipedia.org/wiki/Luhn_algorithm) and no transactions are required to perform the verification.

If it's the former, until you make a transaction there's no way to verify in advance whether or not a card has a still valid account attached to the backside of it.

I know you're saying "without any purchase", but maybe it was just for a vanishingly small amount.

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duskwuff13y ago

> If it's the former, until you make a transaction there's no way to verify in advance whether or not a card has a still valid account attached to the backside of it.

It's possible, with most credit card processors, to perform a $0 authorization to confirm that a credit card number is linked to an active account. It doesn't guarantee that any charges against the card will go through -- the card may be at its limit, for instance -- but it will correctly reject numbers that are structurally valid (e.g, pass Luhn) but which don't correspond to any account.

zalew13y ago

it's just that they offer a free trial without charging any 0.01, if it passes they cancel the account and the owner never knows the card was tried out. this method can work on any 'free trial cc required' as long as it doesn't charge any test ammount.

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