How To Find If A Credit Card Is Fake?

The process is quite simple. Using little bit of Math, and following the step by step instructions given below, you can easily find if a card (debit or credit) is authentic or not.

Let’s take the example of the card shown below. The card number is 4000 0012 3456 7899.

Steps to Identify If a Credit Card Is Fake or Authentic using Luhn Algorithm

The algorithm used to check the authenticity of a card is called the Luhn algorithm, after IBM scientist Hans Peter Luhn (1896-1964). He was given US Patent for this technique in 1960.

1) Note down the card number after removing check digit.

In our example card, we’ll remove the last digit and note down the remaining numbers.

4

0

0

0

0

0

1

2

3

4

5

6

7

8

9

2) Starting from the first digit, multiply every alternate digit by 2. 
Applying this on the digits below,

4×2

0

0x2

0

0x2

0

1×2

2

3×2

4

5×2

6

7×2

8

9×2

we get,

8

0

0

0

0

0

2

2

6

4

10

6

14

8

18

3) If any of the number so obtained is 10 or greater than 10, subtract 9 from it. In other words, if it is a two digit number, subtract 9 from it. 

So we get,

8

0

0

0

0

0

2

2

6

4

1

6

5

8

9

4) Add all the digits together.

Adding all the digits obtained in step 3, we have the answer as 51.

5) Add the check digit that was removed in first step, to the answer obtained above.

Check digit that we removed earlier is 9, and the answer obtained in last step is 51. Adding these two we get the final answer as 60.

6) If the final answer is divisible by 10, the card is valid.

Since our answer 60 is divisible by 10, so it seems that our card is valid.

But wait!!

This doesn’t mean that this is an authentic card for sure. It only means that this can be a possible card sequence. However, whether or not a company has issued a card with this sequence is a different case.

Note: This holds true for debit card as well.

Why don’t you try this out with your card?