Forget looking at holograms, checking the signature, running your finger over the embossed numbers, there’s a much easier way of checking to see if a credit card is fake, and we here at Shoppersbase are surprised that the credit card companies have not told you about it. There is a secret within the credit card industry that every single credit card number has to conform to something called the ‘Luhn’ algorithm. So what is this Luhn algorithm? Basically it is a set of rules that states a certain group of numbers, like a set of credit card numbers, when added in a particular way, should always be divisible by 10. So it is a formula that means you can check any credit card number in an instant, without any specialist knowledge, or having to belong to the CIA or the fraud squad. Here’s how you do it. You can check with your own credit card, or use the one we have provided below, with our figures so that you can easily follow what is going on:
Looking at the last set of four figures, you always start with the second to last number going from the right, in this case a 7, and take this number and moving along now to the left you take every other number and double it. So instead of:
4 5 7 8 4 5 6 2 5 6 4 3 9 1 7 3
You’ll now have
8 5 14 8 8 5 12 2 10 6 8 3 18 1 14 3
Now what you have to do is take any double digit numbers and add them together to make a single one so 14 would be 1+4 = 5, 12 would be 1+2 = 3 and so on. Do this until every double digit number is now a single one.
Now the figures should look like this:
8 5 5 8 8 5 3 2 1 6 8 3 9 1 5 3
Now add up all of these single digits (8 plus 5 plus 5 plus 8, etc) and you should have a total figure.
Is the sum for your card divisible by 10? All credit, debit and bank card numbers are.
That’s why it’s also called a “Mod 10 check.” If it isn’t divisible by 10, you either miscalculated (perfectly understandable), or you somehow got your hands on a fake. This one is real however and you should have arrived at a total of 80, if you did not keep checking. But try it on your own credit card if you do not believe us and you can also Google the Luhn Algorithm to make doubly sure.
Now go tell your friends you’re psychic/a genius and wow them with this little trick.
And if you want to double check our credit card you can always pop the numbers into this online checker: Luhn Algorithm Checker