Peter Hans Luhn was a scientist at IBM. In 1954 he requested a patent of his Luhn algorithm. In 1960 it was granted.

This algorithm is used to validate credit card numbers, among other sets of numbers, to ensure that they have been typed in correctly BEFORE authorization for approval is requested. Most credit card companies, like VISA, Mastercard, AMEX use it to cut down on approval time if the card has not been typed in properly. Get your credit card out and try it if you like.   

Luhn Algorithm - Validating credit card numbers among other things since 1954

Enter your Card Number here (no blanks - no dashes):
Card Type:
Expiration Date: Month Year (Range: 1997~2020)

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