What Is Credit Card Number? A Brief Guide

28 APRIL, 2023

Each credit card is defined by a number ranging from 15 to 19 digits. In India, most credit cards usually have 16 digits on their front side. This number is unique to every customer or cardholder.

How are Numbers on a Credit Card Generated?

The Luhn algorithm is used to generate credit card numbers. The algorithm was established in the 1960s mainly to validate Social Security numbers and credit cards. Today, a credit card number is valid only if it passes the Luhn Check.

Information on the Credit Card

Most people find the long credit card number digits extremely confusing. Do remember, each digit of the number is relevant as it defines the card type, use and security. Here is a quick guide to understand that number and other details on your credit card. 

The Front Digits and Numbers of Credit Cards

The sixteen-digit credit card number, which is on the front of the card, holds great significance.

• The first digit signifies the type of card. It is also known as the 'Major Industry Identifier' or the MII. The American Banking Association assigns the starting number.
  • 3 means a Travel or entertainment card. It also is the first digit of an American Express card.
  • 4 means it is a Visa card.
  • 5 means it is a Mastercard.
  • 6 means it is a Discover card.
• The next five digits of the sixteen-digit number signify the bank that has issued the card. This number is also known as the credit card BIN number. These five digits enable any transaction that takes place via the bank.
• The next nine digits or the 7th to 15th digits, represent the account number.
• Mathematical calculations will calculate the remaining digit on a 16-digit card or the check digit. An algorithm selects the check digit to prevent fraud and card theft.

Relevance of the Check Digit

• Hackers usually try to guess a card number by inputting details related to the account. The randomly-selected check digit is an attempt to prevent such hacking.
• Check digits help prevent errors that may be caused when people type in their numbers.

The Information on the Back of the Credit Card

The back of a credit card has a magnetic strip, hologram, bank details, the account holder's signature, and the card network's logo. Here is a quick guide to this information:

• One of the most important numbers on the back of a card is the CVV number. CVV stands for Card Verification Value. It is a 3 or 4 digit security code used by banks to authenticate the user, especially with online transactions.
• The expiration date is the date that the bank assigns to the card. It adds a step to the verification process.
• The hologram is also a security feature on credit cards. It is unique to every card, and its image changes with a change in angle.

Credit Card Number and Credit Card Account Number

Have you ever wondered if your credit card and account numbers are the same? They are not the same, but they link to one another. When you change your credit card, the number on the new card might change, but your account number will always remain the same.

Credit Card and its PIN Number

One number that is associated strongly with the credit card but never printed on it is its PIN or  Personal Identification Number. Only the cardholder should know the credit card’s PIN.

When you apply for a new credit card, the bank sends you a PIN separately and securely. You are supposed to memorise that number and discard the paper containing the Pin. This process ensures nobody else gets to read that number.

In case you feel somebody knows your PIN, change it immediately to avoid misuse. 

Online credit card security

The vulnerability to theft and misuse increases when you use a credit card online. It is common for phishers to hack into accounts and access credit card information. There are many steps you can take to avoid credit card theft, misuse and hacking.

• Ensure you are using a safe platform every time you use your credit card online. Check the URL - a website starting with "HTTP" may not be safe, whereas "HTTPS//" usually signifies a site is secure and has SSL (Secure Sockets Layer) encryption.
• Follow the practice of regularly updating the antivirus on your computer and protecting it from malware. Viruses allow hackers to break into your account and steal important account information.

Conclusion

You should know what the numbers on your credit card mean to use it safely and securely. As hacking and phishing occur rampantly, awareness of the details enables you to improve the safety of your credit card information.

The credit card number seems very long-winded, but it contains a lot of important information. That is why you must never share the number on your credit card with any unknown person. Also, you should use the card only on secure websites. Basic precautions like these will ensure your credit card stays safe and secure.