If you are doing online business I am sure you have researched a a certain customer that looks questionable. One trick I learned is to put their email in Facebook and see if they have a profile. If not, then most likely it’s a fake or new email used for fraud. If this isn’t enough then try to call the number they gave when signing up. If they are out of the country this can be double tricky for the first to. Another trick is to check the card type:

0 – ISO/TC 68 and other future industry assignments
1 – Airlines
2 – Airlines and other future industry assignments
3 – Travel and entertainment and banking/financial
4 – Banking and financial
5 – Banking and financial
6 – Merchandising and banking/financial
7 – Petroleum and other future industry assignments
8 – Healthcare, telecommunications and other future industry assignments
9 – National assignment

If it’s not a bank card, that should be cause for concern.

Next is to check the type:

The first six digits of a card number (including the initial MII digit) are known as the issuer identification number (IIN). These identify the institution that issued the card to the card holder.

If the type does not match the country that is cause for concern.

Issuing network IIN ranges Active Length Validation
American Express 34, 37 Yes 15 Luhn algorithm
Bankcard 5610, 560221-560225 No 16 Luhn algorithm
China UnionPay 62 or 88 Yes 16-19 no validation
Diners Club Carte Blanche 300-305 Yes 14 Luhn algorithm
Diners Club enRoute 2014, 2149 No 15 no validation
Diners Club International 300-305, 309, 36, 38-39[9] Yes 14 Luhn algorithm
Diners Club United States & Canada 54, 55 Yes 16 Luhn algorithm
Discover Card 6011, 622126-622925, 644-649, 65 Yes 16 Luhn algorithm
InterPaymentTM 636 Yes 16-19 Luhn algorithm
InstaPayment 637-639 Yes 16 Luhn algorithm
JCB 3528-3589 Yes 16 Luhn algorithm
Laser 6304, 6706, 6771, 6709 Yes 16-19 Luhn algorithm
Maestro 5018, 5020, 5038, 5612, 5893, 6304, 6759, 6761, 6762, 6763, 0604, 6390 Yes 12-19 Luhn algorithm
Dankort 5019 Yes 16 Luhn algorithm
MasterCard 50-55 Yes 16 Luhn algorithm
Solo 6334, 6767 No 16, 18, 19 Luhn algorithm
Switch 4903, 4905, 4911, 4936, 564182, 633110, 6333, 6759 No 16, 18, 19 Luhn algorithm
Visa 4 Yes 13, 16 Luhn algorithm
Visa Electron 4026, 417500, 4405, 4508, 4844, 4913, 4917 Yes 16 Luhn algorithm

Posted by Charles Yarbrough

Charley has been working as a webmaster since 1998. Since then, he has had his hands in thousands of websites and has helped millions get online through a company he partially owns called Web Host Pro.

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