22tarush
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Have you ever wondered
what Credit Card numbers mean?
If the answer is yes then this Thread
is for you.
Let's Decode it...
The First Number(s) -:
It is used to tell the General Industry the card belongs to a.k.a Major Industry Identifier (MII)
1 - for Airlines
2 - for Airlines & Financial
3 - for Travel and Entertainment (including American Express)
4 - for Banking and Financial (Visa)
5 - for Banking and Financial (MasterCard)
6 - for Merchandising and Banking (Discover)
7 - for Petroleum
8 - for Health Care and Communications
In India, the first number from 3-6 is what actually matters and is widely known.
Numbers 2-6 -:
These are referred to as the card’s Issuer Identification Number (IIN) and further indicates which credit card company it originates from and clarifies to which card network it belongs. This is to identify the institution that issued the card.
Taking the example of the 2 biggest issuers in India - The series followed by VISA cards starts from 4xx while that of Mastercard starts from 51–55 as the prefix.
Numbers 7-15 -:
This is assigned specifically to you or in easy words it denotes your Credit Account Number.
The Last Digit or The 16th Number -:
The last digit is known as the Check Digit. This number is used to determine the overall number's authenticity and rule out any invalid numbers.
The check digit is mathematically determined based on all the other digits and is created by a formula known as the "Luhn Algorithm."
Here is the Logic behind calculating The Last Digit -:
Step 1: Let’s consider the card number as 1802909582961827
Step 2: As of now, just consider the first 15 digits i.e., 180290958296182|7
Step 3: Now beginning from the left, start with the first number, take every second number(1 8 0 2 9 0 9 5 8 2 9 6 1 8 2), and multiply it by 2 as shown here -Starting from the first and taking every second number, we will get the following numbers: 1 0 9 9 8 9 1 2
1 * 2 = 2
0 * 2 = 0
9 * 2 = 18
9 * 2 = 18
8 * 2 = 16
9 * 2 = 18
1 * 2 = 2
2 * 2 = 4
Step 4: Sum up the digits if the multiplication results in a 2-digit number. i.e., 18 => 1 + 8 = 9
This will give us all the results in a single-digit number.
So, we get : 2, 0, 9, 9, 7, 9, 2, 4
Step 5: Now, Sum up all the single digits and all the digits left in the card number.
i.e., 2+0+9+9+7+9+2+4 + 8+2+0+5+2+6+8 = 73
Add the sum together. Now, what must be added to the sum obtained so that it is divisible by 10? In this case, it is 7
So, 73+ 7 = 80 which is divisible by 10.
This last digit so obtained is called a Checksum digit.
Well, it's complicated at first but quite simple to understand.
Thank you for the Read!
Please let me know if you enjoyed reading this,
Follow for more such content.
what Credit Card numbers mean? If the answer is yes then this Thread
is for you.Let's Decode it...
The First Number(s) -:
It is used to tell the General Industry the card belongs to a.k.a Major Industry Identifier (MII)
1 - for Airlines
2 - for Airlines & Financial
3 - for Travel and Entertainment (including American Express)
4 - for Banking and Financial (Visa)
5 - for Banking and Financial (MasterCard)
6 - for Merchandising and Banking (Discover)
7 - for Petroleum
8 - for Health Care and Communications
In India, the first number from 3-6 is what actually matters and is widely known.
Numbers 2-6 -:
These are referred to as the card’s Issuer Identification Number (IIN) and further indicates which credit card company it originates from and clarifies to which card network it belongs. This is to identify the institution that issued the card.
Taking the example of the 2 biggest issuers in India - The series followed by VISA cards starts from 4xx while that of Mastercard starts from 51–55 as the prefix.
Numbers 7-15 -:
This is assigned specifically to you or in easy words it denotes your Credit Account Number.
The Last Digit or The 16th Number -:
The last digit is known as the Check Digit. This number is used to determine the overall number's authenticity and rule out any invalid numbers.
The check digit is mathematically determined based on all the other digits and is created by a formula known as the "Luhn Algorithm."
Here is the Logic behind calculating The Last Digit -:
Step 1: Let’s consider the card number as 1802909582961827
Step 2: As of now, just consider the first 15 digits i.e., 180290958296182|7
Step 3: Now beginning from the left, start with the first number, take every second number(1 8 0 2 9 0 9 5 8 2 9 6 1 8 2), and multiply it by 2 as shown here -Starting from the first and taking every second number, we will get the following numbers: 1 0 9 9 8 9 1 2
1 * 2 = 2
0 * 2 = 0
9 * 2 = 18
9 * 2 = 18
8 * 2 = 16
9 * 2 = 18
1 * 2 = 2
2 * 2 = 4
Step 4: Sum up the digits if the multiplication results in a 2-digit number. i.e., 18 => 1 + 8 = 9
This will give us all the results in a single-digit number.
So, we get : 2, 0, 9, 9, 7, 9, 2, 4
Step 5: Now, Sum up all the single digits and all the digits left in the card number.
i.e., 2+0+9+9+7+9+2+4 + 8+2+0+5+2+6+8 = 73
Add the sum together. Now, what must be added to the sum obtained so that it is divisible by 10? In this case, it is 7
So, 73+ 7 = 80 which is divisible by 10.
This last digit so obtained is called a Checksum digit.
Well, it's complicated at first but quite simple to understand.
Thank you for the Read!
Please let me know if you enjoyed reading this,
Follow for more such content.
