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

Technically yes, the more detailed information you can obtain about the game, the more precisely you can estimate where the house edge is at any time. The concept of diminishing returns is still present though. For example, the difference in the effect of a 2 or 3 being removed from the remaining shoe, for all practical purposes, is effectively the same.

However, when tracking individual cards, the math starts getting extremely complicated, and easily impractical in live games due to the time it takes.