What does mastercard number start with

When you swipe a credit card, the number is sent to the processor for verification, in part to determine whether the digits conform to the so-called Luhn algorithm. It can quickly identify mistakes when numbers are manually transcribed — for example, if you mistyped your credit card number during online shopping.

If you want to get really nerdy, check your own cards with the Luhn algorithm, which employs simple math but is a little tricky to explain:. For a card with 16 digits, which includes Visa, Mastercard and Discover cards:. Double every other digit, starting with the first digit, and write down the resulting series of numbers. Add together the individual digits that you wrote down.

If you have a two-digit number, combine those two digits before adding. For instance, say you doubled a 7 to get 14 — add the 1 and 4 to get 5, and then use that 5 in your total. Go back to your card number and add up the digits you ignored, including the last digit no doubling. If the result ends in a zero, the card is valid. If the card has 15 digits, namely an American Express card in the U. Use an online calculator for the Luhn algorithm, such as one found here. It may not make you the life of the party, but you might at least raise a few eyebrows.

Mobile Newsletter chat dots. Mobile Newsletter chat avatar. Mobile Newsletter chat subscribe. Prev NEXT. Personal Finance. The front of your credit card has a lot of numbers -- here's an example of what they might mean. Simply noting the first digit of the credit card account number can help you narrow down or identify the issuer.

Credit cards, such as MasterCard, Visa, and Discover, all have unique, identifying numbers as their first digits, with the exception of American Express, Diner's Club and Carte Blanche, which share the same first digit: the number 3. MasterCard's unique first digit is 5, while Visa's is always 4. A Discover card's first digit is consistently the number 6. You can further identify credit cards that start with the same first number by analyzing two or more digits. For example, even though American Express, Diner's Club and Carte Blanche all start with the number 3, you can confirm American Express numbers if the first digit, 3, is followed by a 4 or a 7.

However, if a zero, 6 or 8 follow the 3, the credit card number belongs to a Diner's Club or Carte Blanche account. Some of the more common issuers of cards have between 13 and 16 digits.