What are the Odds of Being Dealt Blackjack?

BlackjackBlackjack is literally and metaphorically the name of the game. It is the best hand that the player can get and unless the dealer magically happens to have it as well it is going to be a winner.

Obtaining a blackjack typically pays out enhanced odds of 3/2 and these boosted wins have a huge impact on your overall profitability. This point is shown by the large impact a lower payout, be it 6/5 or even sometimes lower, has on the house edge.

But just what are the odds of being dealt a blackjack, or a natural as it is sometimes called? How likely are you to land the dream hand and does that differ from the dealer’s chances?

Odds Of Hitting Blackjack

Blackjack is the best hand in the game of blackjack, as hopefully anyone who has ever played the game will know. This hand consists of a two-card 21, meaning an ace combined with either a 10, a jack, a queen or a king. Saying “winner, winner, chicken dinner” each time you hit a natural is optional… but perhaps not advised.

Maths Background Chalkboard

The odds of getting blackjack vary slightly according to how many decks are being used but to give a really short, simple answer, you have just under a 5% chance of getting 21 with your first two cards. We are reliably informed by people who can only be described as maths and blackjack nerds, that the formula to calculate this more accurately is:

2*(4/13)*(4n/(52*n-1))

Where “n” equals the number of decks, this gives a probability of 4.75% based on a six-deck shoe. If we drop down to just a single deck then the chance of getting a blackjack increases very slightly (though this is statistically significant in terms of the house edge of games with fewer decks) to 4.83%.

However we tweak these numbers within the realms of a normal number of decks (eight or fewer), the numbers do not change all that much. So whilst that percentage chance stays at around the 4.7% to 4.8% mark, you can expect to be dealt a blackjack approximately once every 20 to 21 hands.

How many hands per hour you will play depends chiefly on how many players are seated at the table and whether you are playing with a real dealer or at an online casino powered by a random number generator (as opposed to a live online casino). However, a figure of 80 seems fairly reasonable, so you can expect, on average, to be dealt a most pleasing blackjack round about four times per hour.

To be a little more precise, we can see the very slightly changing odds based on games with one to eight decks inclusive in the table below, which is slightly more accurate, going to three decimal places:

Number of Decks Percentage Chance of Blackjack
8 4.745%
7 4.747%
6 4.749%
5 4.752%
4 4.757%
3 4.764%
2 4.780%
1 4.827%

What Are The Odds The Dealer Will Get A Blackjack?

If we have no knowledge of any other cards that have been dealt then the dealer’s chances of making a blackjack are exactly the same as those of a player. The interesting thing about blackjack that makes it different from most other casino games is that each card that is dealt alters the probabilities relating to future cards. In other words, what has gone before impacts what is yet to come.

Dealer Holding Ace

This is different from roulette, dice and other casino games and it is this central principle that makes card counting possible (if very difficult) in blackjack. However, when we are discussing the odds of getting blackjack in this feature we are assuming that there is no counting or even observation going on. In other words, the probabilities are based solely on the pre-deal known facts, which are the number of aces, 10s and other cards.

However, one obvious time it is worth looking at cards that have been dealt is when it comes to the dealer’s up card. Ignoring the cards dealt to any other players, what are the odds of the dealer getting blackjack if, for example, their first card is an ace?

Again, the odds vary very slightly according to how many decks are being used but for the sake of simplicity we will assume you are lucky enough to have found a single-deck game. If the dealer gets an ace then they need a 10, a jack, a queen or a king to complete their blackjack. There are 16 successful combinations out of a remaining 51 cards.

So, if the dealer draws an ace first up, the probability of them getting a blackjack is 16/51, or 31%. That means that they would expect to complete the blackjack slightly less than one in three times they get that ace. Whilst it is all too easy to be fearful when the dealer is showing an ace the reality is that far more often than not, 35 times out of 51 in fact, they will fail to land the BJ. Indeed, that is why insurance is such a bad bet.

A similar equation applies should the dealer get a card worth 10 for their up card. In this scenario they need an ace to hit blackjack, of which there are four. So four out of the remaining 51 cards means they have a probability of 4/51 – or 7.8%. With a 10 (or a jack, a queen or a king), you can expect the dealer to make their blackjack approximately once in every 13 times.

Dealers Up Card Chance of the Dealer Getting Blackjack
Ace 31%
Ten, Jack, Queen, King 7.8%
Any Other Card 0%