I don’t know about you, but it irritates me wildly when the service says that it has a free trial, but asks for my card number. So, just in case. Hoping, it's likely that I will forget the expiration day of the trial, and I will be charged a month or a year of the subscription fee. A subscription fee for a service that I could have forgotten about. By the way, this happened to me more than once.
So I couldn't find a better way to try paid services than to enter fake credit card numbers. (real active credit card numbers with money)
Just entering the left 16 digits is not an option, since all the digits mean something - country, bank, etc. and should be more or less by the rules. So I recommend using the GetCreditCardNumbers service.
You just need to choose what type of card you want to enter: Visa, MasterCard, American Express and Discover and copy one of the numbers from the main page of the service for yourself. Each reboot you get a new pack of numbers.
If you need a block of numbers for some other purpose, the service can return them to you in JSON.