How can I use regex to validate credit card numbers?

How can I use regex to validate credit card numbers?

You can use a regex pattern to match the format of credit card numbers. For example, a common pattern is ^(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|6(?:011|5[0-9]{2})[0-9]{12}|3[47][0-9]{13}|3(?:0[0-5]|[68][0-9])[0-9]{11}|7[0-9]{15})$.

What does this regex pattern do?

This pattern checks for various credit card formats, including Visa, MasterCard, American Express, and others, ensuring they have the correct number of digits.

Can you explain how to implement this in Python?

Sure! You can use the re module in Python. Here's a simple example:

import re

pattern = r'^(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|...)$'

def validate_credit_card(card_number):
    return re.match(pattern, card_number) is not None