If card counting in blackjack is just keeping track of high cards vs low, does that mean if I could remember all the different cards used (i.e. how many 5s, how many 7s) I would be really good at blackjack?

Question

This would break online casinos because you could easily do that with electronics. Assuming the casino itself is playing fair.

If you could perfectly keep track of how many of which cards are left in the decks, and everytime make the most mathematically sound bet, would the house still have an edge?

(I assume the correct answer will start off saying I don’t understand how card counting works – fair enough, but what about the basic explanation of it did I misinterpret?)

In: Mathematics

Answer 1

>If you could perfectly keep track of how many of which cards are left in the decks, and everytime make the most mathematically sound bet, would the house still have an edge?

Your understanding of card counting is correct — keep track of the cards that have been played, use that information to figure out the odds of your success (or failure), then adjust your betting to improve your odds of losing small (…and thereby winning big), ie: don’t raise when your odds of success are low, raise when your odds are higher.

The more cards you *see* played, the better you know the cards that are left, and the stronger your model becomes. Let’s say from a fresh deck, you are dealt a 12 and you don’t see any face cards or 10’s on the table. You have *almost* no idea if hitting on your 12 will bust or not. Later in the game, from that same unshuffled deck, if all face cards and tens have been played, you can be 100% certain that hitting on 12 won’t bust.

In order to maintain quick play (not have to shuffle between every hand) *and* somewhat foil card counters, casinos use multiple decks. So instead of keeping track of the cards in 1 deck, you now have to keep track of the cards in 4+ decks. As before, at the beginning your model will be weak and it will get stronger until the decks are shuffled again.

>This would break online casinos because you could easily do that with electronics. Assuming the casino itself is playing fair.

Card counting *only* works when you are playing from a *known* deck of cards. With online casinos there are no decks. Every hand is ‘shuffled’, so any model you make can only be made from the cards you *see currently* on the table, and that doesn’t give you much information about what cards are left to be played. Essentially, card counting doesn’t work with computerized games.