| Have you ever really looked at your credit card and | | | | check digit is a number that is calculated by applying a |
| tried to figure out what that huge string of numbers | | | | special formula to all of the other numbers. The check |
| really means? Do these card issuers have so many | | | | digit is the result of that formula and is used as an |
| customers that your account number has to be 16 | | | | anti-fraud check. |
| digits long? | | | | To keep things from getting too confusing, look at your |
| You may be surprised to know that all those numbers | | | | card as you follow along for the next steps. |
| you see actually do stand for something, and it's not | | | | American Express |
| just who you are. Let's take a look. | | | | The American Express Card uses digits three and |
| Most of the major credit card companies operate on | | | | four for type (business or personal) and the currency |
| the same system when choosing a credit card | | | | of the cardholder's country of origin. The next digits |
| number. Other cards like gas cards, department store | | | | from the fifth through the eleventh are account |
| cards and phone cards go their own way. Let's | | | | numbers. |
| concentrate on the ones that all play by the same | | | | Digits twelve through fourteen indicate the card |
| rules. | | | | number within the account and the last digit is the |
| The very first digit in the series will be a 3,4,5, 0r 6. This | | | | check digit. |
| number designates the type of card as follows: | | | | Visa |
| 3 = a Travel & Entertainment Card like American | | | | With Visa, digits two through six represent the bank |
| Express or Diners Club. | | | | number. Beginning with the seventh digit and running |
| 4 = Visa and Visa-branded debit cards, cash cards, | | | | through the twelfth or the fifteenth represents the |
| etc. | | | | account number and the last number is the check digit. |
| 5 = MasterCard and MasterCard-branded debit cards, | | | | Since all Visa cards do not have the same amount of |
| cash cards, etc. | | | | numbers in the sequence, the number of digits in a |
| 6 = Discover | | | | group may vary. |
| American Express and Diners Club use the second | | | | MasterCard |
| digit to identify the company. That means that Diners | | | | For MasterCard, the second digit, through to anywhere |
| Club cards will start with either "36" or "38", and | | | | between the third and the sixth digit is the bank |
| American Express cards will use either "34" or "37". | | | | number. All remaining digits, except the check digit at |
| The remaining numbers in the series are used for | | | | the end of the series, identifies that cardholder's |
| different purposes depending upon the card type and | | | | account. |
| issuer. | | | | Now that we've gone over it all, you're probably |
| In most cases, the next group after the opening series | | | | wondering why you were ever wondering in the first |
| of numbers represents the routing number of the | | | | place. Just remember though, knowledge is power. |
| card-issuing bank, the group after that is the user's | | | | Some things are just fun to know. |
| account number, and the final digit is a check digit. The | | | | |