Logic behind credit card numbering

Have you ever thought about the logic behind credit card numbering? This numbering idea gives easy ways to identify & classify billions of transactions done every day.

Number on your credit card

Every number on your credit card has its own relevancy. Following are some interesting facts about credit card numbers.

Do you know that the first digit of a credit card will be always 3, 4, 5 or 6. It helps to you identify the card you have.

What does First Digit stand for

• 3 - Entertainment or Travel card like American Express or Diners Club
• 4 - Visa Cards
• 5 - Master Cards
• 6 - Discover Cards

The other numbers are usually used to identify other purposes depending upon the card issuer. In general the remaining numbers are grouped to identify the routing number of the bank and the user details. The secret about the last digit is that is a automatically generated special number upon a formula, which is used by the card issuer to find a fraud.

Each number after 1st digit have different meaning depending upon the card type.

It can give simple information like Country of origin, primary card or not, bank details.