All mainstream credit card numbers obey a mathematical trick designed to catch the most common typos. It’s called the Luhn ...

Your credit card account number forms part of your card number, but the two are not the same. Credit card account numbers are often shorter, but they are always completely unique to you.

You’re at the checkout screen after an online shopping spree, ready to enter your credit card number. You type it in and ...

Protecting your credit score. Keep utilization below 30% of credit limit. In most cases, a lower utilization means a higher credit score—with 0% utilization being the exception.

Printed on a credit card, you'll find the card number, the cardholder’s name, when the card expires and the card's security code — all the details you need to make purchases online or in person.