Six-deck and eight-deck blackjack are the most common configurations seen on the casino floor today. You guessed it  these variants use six and eight standard decks, amounting to 312 and 416 cards, respectively. The increased number of decks further tilts the odds to benefit the house.

In conclusion, the number of decks used in blackjack can vary. Traditional games use a single deck, while many casinos use multiple decks in a shoe. The use of multiple decks can affect the odds of the game and make it more difficult for players to use card counting strategies.