How to Determine if a Credit Card Number is Valid Fresh Deals Alert

How to Determine if a Credit Card Number is Valid

Credit cards use the Luhn Check DigitAlgorithm. The main purpose of the Luhn Check Digit Algorithm is to catch data entry errors, but it does double duty here as a weak security tool.

                                 The Luhn Check Digit Algorithm

For a card with an even number of digits, double every odd numbered digit (1st digit, 3rd digit, 5th digit, etc…) and subtract 9 if the product is greater than 9.

Add up all the even digits (2nd digit, 4th digit, 6th digit, etc…) as well as the doubled-odd digits, and the result must be a multiple of 10 or it’s not a valid card
If the card has an odd number of digits, perform the same addition doubling the even numbered digits instead.

HEY ENJOY THIS ARTICLE? ! Subscribe to my Blog Feed in a feed reader or sign up for Free Email Updates and you'll never miss a single post. Thanks for reading my Post!

Delivered by
Enter your email address in the Box below to Receive Regular Updates in your Mailbox. Your email address is secured with us:

Delivered by

No comments :

Post a Comment

Search This Blog