Payment card

Validate

• JavaScript library
• Python library
• Go library2 cases fail
• Ruby library3 cases fail
• Rust library2 cases fail
• .NET library2 cases fail
• Erlang library

Validates a payment card number (credit or debit): 12 to 19 digits and a Luhn check digit.

• The function does not detect the brand, look up the issuer range, or check the expiry or the CVV.
• The function rejects a number whose digits are all the same, even though it passes Luhn.
• Accepts a string or a number. The mask characters (whitespace, ., - and /, the set the CPF and CNPJ accept) go between any two digits, a run of them included (4111 - 1111 - 1111 - 1111), because the printed grouping changes with the brand (4-4-4-4, 4-6-5, 4-6-4). Whitespace around the value is ignored.
• Any other character makes the number invalid instead of being dropped: letters (4111a1111b1111c1111), ,, _, parentheses, or a mask character that is not between two digits (a leading -, a trailing .).
• A number is accepted only when it is a non-negative safe integer. A number above 2^53 - 1 has already been rounded when it arrives, and a negative or fractional one is not a card number, so pass a longer number as a string.

import { isValidCreditCard } from '@brazilian-utils/brazilian-utils';

isValidCreditCard('4111111111111111'); // true (Visa test number)
isValidCreditCard('5555555555554444'); // true (Mastercard test number)
isValidCreditCard('378282246310005'); // true (American Express test number)
isValidCreditCard('4111 1111 1111 1111'); // true (spaced mask)
isValidCreditCard('4111 - 1111 - 1111 - 1111'); // true (a run of separators between the digits)
isValidCreditCard('4111.1111/1111-1111'); // true (any of the mask characters)
isValidCreditCard('4111111111111112'); // false (bad check digit)
isValidCreditCard('0000000000000000'); // false (every digit the same, though the Luhn check passes)
isValidCreditCard('4111a1111b1111c1111'); // false (letters between the digits)
isValidCreditCard(4111111111111111111); // false (above 2^53 - 1, pass it as a string)