A credit card number -- the long and seemingly random series of numbers on most credit cards -- is used to identify the card and account holder. While there is some generic, identifiable information in every credit card number, it’s best to keep your credit card numbers secure. We break down how to decipher your own credit card number and all of the things you can do to keep your financial information safe.
How a credit card number works
Most credit card numbers are made up of 16 digits, often bunched together in sets of four. American Express card numbers contain 15 digits, however, and some companies use 19 numbers. Here are some of the other components embedded in those numbers:
- Major Industry Identifier: The first number of a credit card number is known as the Major Industry Identifier, or MII. This number indicates what type of institution issued the card.
- Issuer Identification Number: The next five numbers are referred to as the card’s Issuer Identification Number, or IIN -- previously known as the Bank Identification Number, or BIN. This number identifies the institution that issued the card.
- Individual card account: The next nine to 12 numbers identify the individual account. Having that many digits creates a huge number of numerical possibilities for each issuer to use for their cards, according to Discover.
- Checksum: The last digit of a credit card number is known as a checksum, which immediately detects if the card number is incorrect thanks to a special algorithm.
How to protect your credit card number
Credit card numbers should be protected, and there are several ways to do so. First, never share your account information -- not even over the phone with a representative from the credit card issuer unless you placed the call.
You should also be cautious when shopping online. Use a private device, a secure connection and don’t respond to phishing emails when shopping online. Before you checkout, double-check the merchant and the URL of the site to make sure it’s safe. If you suspect fraud, report it right away.
To add an extra layer of security, you can use a third-party digital wallet or a virtual credit card number.
How digital wallets like Apple Pay protect your credit card number
Digital wallets like Apple Pay, Google Pay and Samsung Pay allow you to use your credit card directly from your phone, without needing your card. These apps don’t have access to the original credit card number you give it. Instead, they assign it its own unique code which is encrypted and protected by several layers of security.
Virtual credit card numbers
Virtual card numbers are a convenient way to make credit card purchases online. They are sometimes called virtual credit cards or virtual cards. Thanks to virtual card numbers, you can shop online faster and more securely and you don’t even have to pull out your wallet.
Though not available through all major credit card issuers, you can request a virtual card number using your online account management site.
The bottom line
A credit card number is 16 digits, often appearing in sets of four. It’s used to identify the card and the account holder, and it must fit a complex pattern in order to work. Credit card numbers should be protected, such as through a third-party digital wallet or a virtual credit card number.
The editorial content on this page is based solely on objective, independent assessments by our writers and is not influenced by advertising or partnerships. It has not been provided or commissioned by any third party. However, we may receive compensation when you click on links to products or services offered by our partners.
Correction, 7:30 a.m. PT Jan. 25: We’ve replaced phrases that were not entirely original.
