Illinois is in the Central Time Zone in the United States of America (USA). US Central Standard Time (CST) is 6 hours behind Greenwich Mean Time (GMT-6).
Credit Card Account Number Verification - Card Type Identification. This page provides information about identifying a credit card type from a card number's numeric range and number of digits. First digit must be a 3 and second digit must be a 4 or 7. Valid length: 15 digits. First digit must be 3 and second digit must be 0, 6, or 8. Valid length: 14 digits. Valid length: 16 digits.
For example, the MasterCard system is identified by the number 5, American Express and Diners Club credit card numbers start with the number 3, while Visa and Discover Card systems are identified by the numbers 4 and 6, respectively. Each credit card number has a structure that varies by system. In the MasterCard system, digits two through six are used to identify the bank number, digits seven through 15 designate the account number and digit 16 represents a check digit.