You can read their terms of service from here https://vast.ai/privacy/
So if you are going to buy a debit card it won't work.
Credit card is an English term often used to generalize, in order to include all types of card: debit card, credit card, prepaid card, payment card, charge card, VCC (virtual credit card)
So it doesn't matter and the privacy policy is irrelevant. I don't know why you posted a link to it
Ouch! I had not noticed that.
To be honest I don't know how this whole card system thing works, it looks like a site can choose whether they accept cards from your service/bank or reject all of them?
To make things more complicated, yet more sites such as Vast use a payment backend e.g Stripe, so they (or any company that handles its own payment processing such as YouTube or Netflix) would be able to choose whether they accept the kind of card issued that you have.
Actually how does it even know that I have a debit card (well, nearly bought this) and that prepaiddigitalsolutions issued it? I hate how unlike bitcoin there's so little info to find about how cards work internally.
There is an ISO international numbering standard with credit card numbers.
With the first 4 digit numbers, you can know if the card is a VISA or Mastercard. The first 6 digit numbers represent the BIN (Bank Identification Number)
As for the VCC itself, you need to register to Prepaiddigitalsolution, if you succeed to do it because the website is often buggy. Even if you manage to register, you may struggle to log in when you will want to check your balance or something else. Even if the card is declined your balance is reduced. You will try to contact them so, to explain the card was refused but they still removed the money from your balance; good luck to have an answer, I'm still waiting.
Personally, I got fucked with 100€.
it is not to discourage you but I prefer to warn you