In simple Bin is basically a dummy credit card that is generated and can be used to buy subscriptions from some websites. To create a dummy credit card you need a bin which is actually a 6 or 5 digit number of a credit card. If you have bin visit namso-gen.com ( website to generate dump credit card ). Enter the digits there suppose 515515 and click on the generate option. You will get your dummy credit card details.
To work a bin, copy the dummy credit card that works on that website and paste it in their payment option. ( Please avoid making bins yourself / less chances of suceed ) If your bin works you will easily get their subscription for free without using real credit card.
For official answer you can check the sites mentioned below -
About BIN
This site contains huge tools like, bin checker, bin lists, Credit card generator etc…
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