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[ Valid_CreditCard ]


[Valid_CreditCard] checks the format of an credit card number. If the parameter appears to be a valid credit card number then True is returned. 

Credit card numbers entered into the tag should not have any spaces or punctuation.

This tag uses the ROT-13 algorithm to check the basic validity of a credit card number. It does not communicate with the bank network to check whether a given number is active or has credit available. Use your banking software to authorize credit card transactions.

This tag should return True for all valid credit card numbers from Visa/Mastercard/AmEx/Discover and major banks. It is intended as a first check for data entry and should not necessarily be used to deny purchases.

  • Syntax
  • Beginner

To check the validity of a credit card number:

Use the [Valid_CreditCard] tag. The following example checks a fake credit card number and False is returned.


[Valid_CreditCard: '0000000000000000']



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