http://code.activestate.com/recipes/tags/false/popular/2011-08-11T19:06:58-07:00ActiveState Code Recipes2011-08-11T19:06:58-07:00Stijn de Graafhttp://code.activestate.com/recipes/users/4178055/http://code.activestate.com/recipes/577838-credit-card-validation/

<p style="color: grey"> Python recipe 577838 by <a href="/recipes/users/4178055/">Stijn de Graaf</a> (<a href="/recipes/tags/card/">card</a>, <a href="/recipes/tags/credit/">credit</a>, <a href="/recipes/tags/false/">false</a>, <a href="/recipes/tags/number/">number</a>, <a href="/recipes/tags/testing/">testing</a>, <a href="/recipes/tags/true/">true</a>, <a href="/recipes/tags/validating/">validating</a>, <a href="/recipes/tags/validation/">validation</a>). </p> <p>Test validity of any credit card number using the LUHN method (mod 10). Starting at the last digit and moving backwards, you add up every other digit. Then, you double the left-out digits, and add the digits of these results to the original sum. If this satisfies sum mod 10 == 0 then the card is valid.</p> <p>This is also explained at <a href="http://www.beachnet.com/%7Ehstiles/cardtype.html" rel="nofollow">http://www.beachnet.com/~hstiles/cardtype.html</a></p>