How do you detect Credit card type based on number

Question

I'm trying to figure out how to detect the type of credit card based purely on its number. Does anyone know of a definitive, reliable way to find this?

Answer 1

I searched around quite a bit for credit card formatting and phone number formatting. Found lots of good tips but nothing really suited my exact desires so I created this bit of code. You use it like this:

var sf = smartForm.formatCC(myInputString);
var cardType = sf.cardType;

Answer 2

In Card Range Recognition (CRR), a drawback with algorithms that use a series of regex or other hard-coded ranges, is that the BINs/IINs do change over time in my experience. The co-branding of cards is an ongoing complication. Different Card Acquirers / merchants may need you treat the same card differently, depending on e.g. geolocation.

Additionally, in the last few years with e.g. UnionPay cards in wider circulation, existing models do not cope with new ranges that sometimes interleave with broader ranges that they supersede.
Knowing the geography your system needs to cover may help, as some ranges are restricted to use in particular countries. For example, ranges 62 include some AAA sub-ranges in the US, but if your merchant base is outside the US, you may be able to treat all 62 as UnionPay.
You may be also asked to treat a card differently based on merchant location. E.g. to treat certain UK cards as debit domestically, but as credit internationally.

There are very useful set of rules maintained by one major Acquiring Bank. E.g. https://www.barclaycard.co.uk/business/files/BIN-Rules-EIRE.pdf and https://www.barclaycard.co.uk/business/files/BIN-Rules-UK.pdf. (Valid links as of June 2017, thanks to the user who provided a link to updated reference.) But be aware of the caveat that, while these CRR rules may represent the Card Issuing universe as it applies to the merchants acquired by that entity, it does not include e.g. ranges identified as CUP/UPI.

These comments apply to magnetic stripe (MagStripe) or PKE (Pan Key Entry) scenarios. The situation is different again in the ICC/EMV world.

Update: Other answers on this page (and also the linked WikiPedia page) have JCB as always 16 long. However, in my company we have a dedicated team of engineers who certify our POS devices and software across multiple acquiring banks and geographies. The most recent Certification Pack of cards this team have from JCB, had a pass case for a 19 long PAN.