Double Deck Blackjack

Blackjack : how quickly the odds change with an increase in decks.

Here is a simple demonstration about why it is important to have as few a decks in use as possible:

For demonstration purposes, we shall be using a deck that consists of only 3 cards. The three cards our deck will have in it: Ace, Jack, and Deuce.

We begin play: you are dealt an Ace. There are two cards remaining in the shoe, a Jack and a Deuce. What are the odds of you getting dealt the jack for your second card, giving you a blackjack? They are 1 out of 2: your chance of getting dealt the Jack are 50%.

Next see the dramatic percentage change of getting a blackjack with multiple decks in use.

Okay, now the game has added an extra deck of cards. We now have 2 Aces, 2 Jacks, and 2 Deuces in our shoe.

I deal you an Ace, what are the odds of you getting dealt a Jack to complete a blackjack? They are 2 (Jacks) out of 5 (deck has an Ace, and 2 Deuces that can ruin a chance for blackjack).

Your odds for hitting a blackjack have dropped from a 1 in 2 chance when we were using a single deck. 50%

To a 2 in 5 chance of hitting a blackjack. 40%

A considerable difference. But that is only making the game into a double deck game. Many casinos, most in fact, use a shoe with 6 decks, some as many as 8 or 9. You can see why it is important to find a blackjack game that has as few decks in use as possible.

Blackjack: single deck