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Why the number of decks in blackjack affect you

Why The Number Of Decks In Blackjack Affect You

Blackjack is a popular card game played in online and land based casinos.  This game is also called 21 and is a comparing card game.  Blackjack is played between the player and the dealer, which means that it is the players that compete against the dealer.  Blackjack can be played with one deck of 52 cards or with multiple decks.  The aim of Blackjack is for the player to get 21 with the first two cards that are dealt, to get a higher score than the dealer without going over 21 or the dealer will draw more cards until 21 is exceeded.

It has been said that the fewer decks used the better the odds of winning and the reason for this is that each deck has 1/13th Aces.  It is interesting to note that the reason there will be more Blackjacks in a game with fewer cards is that removing a card from a game with less cards has much more of an impact.

Playing Blackjack with One Deck

Working out the odds of winning in a Blackjack game with fewer cards can be worked out in the following way.  Players must multiply the odds of being dealt an Ace from one deck with the odds of drawing any other card that has a value of ten.  Each deck has 4 Aces plus sixteen cards, 4 Tens, 4 Jacks, 4 Queens and 4 Kings.  This brings the possibility of being dealt an Ace 4 out of 52, which is simplified to 1/13.  Once an Ace has been dealt the chance of being dealt a card worth 10 points is 16/51.

Players can now see that the first number is based on a deck of 52 cards, but players have now taken a card, which means players must work out the odds of taking one of the ten point cards from 51 cards.  The change here is small, but is the main reason why playing Blackjack with fewer decks is beneficial and also gives the house a disadvantage.  For an accurate calculation of the possibility of winning Blackjack from a single deck players must double their result, which could mean that players could actually win with a ten point card or an Ace at the beginning of the game.  The chance of winning Blackjack from a single deck is around 4.83%, and this is worked out by drawing an Ace which is multiplied by the chance of drawing a card valued at ten and then multiplied by two.

Playing Blackjack with Two Decks

The odds of winning Blackjack using two decks are different as players are now playing with 104 cards and not 52.  The chance of winning Blackjack from two decks is 8/104, which means the chance of being dealt a ten point card is 32/103.  Once these two are multiplied and then doubled the outcome is 4.78%.  Online casinos that play with multiple decks are increasing the house advantage and the chances of winning Blackjack are now 0.05% less.

Double Down with Fewer Decks

If players choose to double down they will have more of a chance of being dealt a face card, which offers a greater opportunity to get 21 if there are fewer decks.  The dealer will also benefit from fewer decks and so it is not just the player who will benefit from playing with fewer cards.  With the double down options though, it is only the player that can use this option and not the dealer.

Statistically it would seem that players would benefit from playing Blackjack with fewer cards.