It’s a Visa credit card,while different card types offer different lengths of numerical digits, most major credit card issuers popular in the United States have 16 primary numbers on the front face of the card. Visa, MasterCard, and Discover cards all have 16 digits.


American Express is the only major credit card issuer in the U.S. with one less number – at 15 digits. Regardless of the length of numbers, their numerical sequencing is still guided by the same Luhn validation formula, the mathematical check sum equation that makes all valid credit card numbers error free.


The very first 6 credit card number sequence is known as the issuer identification number (IIN) or bank identification number (BIN). These first 6 numerical digits denote the credit card network and the banking institution the card is a member of. The issuer identifier number also incorporates the card type’s special identifying numerical prefix

The numbers found on credit cards have a certain amount of internal structure, and share a common numbering scheme.

The card number’s prefix is the sequence of digits at the beginning of the number that determine the credit card network to which the number belongs. The card number’s length is its number of digits.

The prefixes and lengths for the most common card types are:

Card Type Prefix(es) Length
American Express 34 or 37 15
BankCard 560–561 16
Diners Club / Carte Blanche* 300–305, and 38 14
Discover Card 6011,6500–6509** 16
JCB 3 16
JCB 1800,2131 15
MasterCard 51–55, 36 14,16
Visa 4 13 or 16

*As of November 8, 2004, MasterCard purchased the domestic (US) Diner’s Club bin range. Diner’s Club International BIN range will remain (starting with 38), but the 36 bin range will now be processed as MasterCards.
**As of October 1st, 2005, Discover Bank will include a new BIN in the range of 650000–650999.

In addition, the first 6 digits of the credit card number are known as the Bank Identification Number (BIN). These identify the institution that issued the card to the card holder.

Some credit card issuers choose to restrict the card numbers they issue to those which pass a checksum test, where the final digit of the card number is used to confirm the initial digits.

This has two benefits of preventing casual attempts to invent credit numbers (only one in ten will be valid), and also prevent mistakes when the card number is manually recorded. The checksum test for credit card numbers is the Luhn formula, described in Annex B to ISO/IEC 7812, Part 1.

American Express, in particular follows the following specific algorithm:

First 4 numbers, country code, currency code and card type (ie charge or credit card)
Next 2, card type (ie gold, platinum)
Next digit, billing cycle
Next 4 digits, account number
Fourth from last, card issue (begins at 1 and will go up if it’s replaced because the card is lost or stolen)
Next two, card issued under the account (ie if there are additional card holders. begins at 00 and increments)
Last number, Luhn-10 check digit (used for verification)

Posted via email from IBFN (Islamic Banking & Finance Network) at Posterous