- Luhn algorithm is used to check if it is a valid number.
- The first digit of credit card number represent the category of entity or Issuer Number
- First six digits of a card number indicate the bank that issued the card.
- Digit 7 to last number minus 1 indicate individual account identifier.
- Last number indicate the check digit.
Validating Credit Card Number
Step1:Double every alternate digit of account starting second digit from right.
Step2:Add the individual digits comprising the products obtained in step1 and each of unaffected digit in the original number.
Step3:The total obtained in step 2 must be a number ending in zero (30, 30,50 etc.) for the account number to be valied.
The sum is 90 so it is valied account number.
The sum is 57 so it is not a valied account number.
0 comments: