Regex for Discover credit card

Question

I have read through this question, but for Discover card, the starting digits are 6011, 622126-622925, 644-649, 65 instead of just 6011, 65. (Sourc

Answer 1

Here are your options:

1. Hack your way through it and build a really complicated regex. Regexes are not suited for this sort of integer comparison so what you come up with will necessarily be long, uncomplicated and unmaintainable. See Regex for number check below a value and similar SO questions on this topic.
2. Use integer comparison in your code.

For reference one such said complicated regex would be

62212[6-9]|6221[3-9]|622[1-8]|62291|62292[1-5]