Cracking The Credit Card Code - What The Numbers on Your Credit Card Mean

• 

  issh on 04/02/2011 - 21:04

  wow that's interesting
  especially the Major Industry Identifier and also the Genuine Check(accumulative number and their doubles, being multiples of 10)

• 

  kcyw on 04/02/2011 - 21:31

  Thanks for sharing. Didn't think the numbers stand for something before, that rule may prove really useful too, didn't know you can check for fake numbers… but still, not too hard to fabricate a number if someone really wanted to.

• 

  bennib0i on 04/02/2011 - 23:55

  interesting read

• 

  c64 on 05/02/2011 - 16:26

  great link!

• 

  altomic on 05/02/2011 - 22:20

  about 15 years ago a friend had a dos program that would generate credit card numbers.

• 

  Aussiekev on 07/02/2011 - 10:43

  Garbage.

  I just checked both of my credit cards and neither add up to be divisible by 10 when applying the double every odd positioned digit and add every even placed digit. And I know for a fact that both of my cards are definitely legit. Maybe this is a US only check or something?

  • 

    retiredfeline on 07/02/2011 - 11:21

    http://www.beachnet.com/~hstiles/cardtype.html

    "Because I get at least a letter a week regarding this routine, here are some additional helpful notes:

    Make sure that you:

    have started with the rightmost digit (including the check digit) (figure odd and even based upon the rightmost digit being odd, regardless of the length of the Credit Card.) ALWAYS work right to left.

    the check digit counts as digit #1 (assuming that the rightmost digit is the check digit) and is not doubled
    double every second digit (starting with digit # 2 from the right)

    remember that when you double a number over 4, (6 for example) you don't add the result to your total, but rather the sum of the digits of the result (in the above example 6*2=12 so you would add 1+2 to your total (not 12).

    always include the Visa or M/C/ prefix."