Wednesday, March 21st, 2018

Blackjack house edge explained

blackjackIt may look like as a simple game where luck plays the biggest role. Of course, blackjack is a game of chance, but there are some decisions that can be made based on mathematical odds to increase the chances of winning.

Because of that, blackjack is known as a game with low house edge – a player knowing the basic strategy can lower the house edge dramatically.

Blackjack house edge – so what is it exactly?

To put it in simple words – the house edge is the representation of the mathematical advantage which a casino holds over the player during the play. The house edge is usually represented by a percentage number which tells a quantified loss for every $100 wagered.

For example: a house edge of 3,5% means that in theory the player is supposed to forfeit $3,5 out of every $100 bet.

Blackjack is a casino game that is famous for having a relatively low house edge. Here are a few examples of the house edge of popular blackjack variants: European Blackjack: 0.39%, Multi-Hand Blackjack: 0.63%, Atlantic City Blackjack: 0.35%, Pontoon: 0.39%, Super Fun 21: 1.30%.

The house edge for classic blackjack in various variations is usually less than 1%.

Just to give you something to compare to, here are some of the most popular casino games with their rough house edge numbers: Baccarat: 1.2%, Roulette: 5.26% for the American version, 2.7% for the European version, Slot Machines: 3%-20%, Keno: 20%-40%.

What contributes to blackjack house edge

blackjackWhen you compare seemingly the same blackjack games, they can have a different amount of expected house edge – some of them may get a higher number, the others, even in spite being the same type of blackjack, may get a lower number.

There are a lot of factors that can vary depending on the type of game played. Also, it is up to casinos to apply some of their own rules to the play.

Take a look at the various factors that can vary between games:

  • Number of decks of cards used
  • Dealer hits or stands on a soft 17
  • Doubling down
  • Player can double on two identical cards
  • Can’t hit split aces
  • Player can resplit aces
  • Split up to four hands
  • Late surrender
  • Blackjack pays 3 to 2
  • Blackjack pays 6 to 5

Below we are going to explain in more detail how do those factors affect the house edge and how to use them in player’s favour.

♠ Standing on soft 17

One example is that the casino can imply a rule of the dealer hitting or standing on a soft 17 (an ace and a 6). If the rule says that the dealer must hit on a soft 17, the house edge increases. Hitting in this situation always increases the chances of winning.

It is therefore also a good tip for players – you should never stand on a soft 17.

To find out whether the dealer in the specific game must stand or hit on 17 all you need to do is check the writing on the table. You can encounter one of the following writings: ‘Dealer must stand on all 17’s’ or ‘Dealer hits soft 17’.

♣ Number of decks of cards used

Another example would be the casino deciding on a number of decks of cards used during the game. Single deck blackjack house edge would be different than double deck blackjack house edge. The online casinos usually decide on using as much as 6 decks of cards.

The number of decks used in particular varieties of blackjack is significant when choosing a strategy and when estimating the casino’s advantage over the player. The general rule is that the fewer the decks, the more likely the player is to win.

This is because when playing with one deck there is a greater chance of occurrence of blackjack and it is easier to use advanced strategies that involve counting cards.

Unfortunately, playing with fewer decks also has its drawbacks – many online casinos do not allow playing with one or two decks at all, and those that offer this type of blackjack, pay much less for the win (for example 6:5 compared to regular one 3:2 for blackjack games with many decks).

♥ Resplitting

When you are dealt with two cards of the same value, you can choose to split them into two separate hands. If once again you happen to have two cards of the same value, some casinos may allow you to resplit them again – for example, you may be allowed to resplit up to 4 hands.

A few casinos may even have a rule allowing players unlimited splits.

The rule is that the more resplits you can do, the lower the house edge gets on the game and the more favourable it is to the player.

♦ Doubling down

The possibility of doubling down has a real impact on the house edge.

First, let us explain what doubling down means. Once you have been dealt two cards, you get an option to double your initial bet, but this means that you will be dealt just one more additional card.

Casinos have various rules regarding doubling down – most casinos allow players to double down on any two cards, some of them only let you do it when the hand totals to 10 or 11.

When you are playing a game that consists of 8 decks and all kinds of doubling down are permitted, the house edge is around half of one percent.

The house edge will decrease by .13% to 0.42% when the rules state that double downs are allowed after splitting. Another example is that the house edge increases by .21% to 0.76% when double downs are restricted.

As you can see, all varieties have their advantages and disadvantages, and casinos always try to get the most advantage over the player.

Since each game can have a totally different set of rules, the house edge for each one of them varies depending on that. Even in spite of the type of blackjack being exactly the same!

Blackjack house edge calculator

calculatorThere are dozens of factors that matter when trying to calculate the house edge for a specific type of blackjack. Changing even one of the factors can completely change what the house edge of the game is.

To make things easier for players, the technology comes to rescue. Using an online blackjack house edge calculator allows players to calculate this number quickly and without any hassle. Usually such calculators have a set of rules mapped out, all you have to do is tick the correct boxes.

Once you are done with ticking the right rules for the game you wish to play, you are immediately presented with the estimated house edge.

You can expect to receive three various results:

  • Optimal results – this result is based on an optimal composition dependent strategy as well as cards being shuffled after every hand (which doesn’t happen at online casinos as they use multiple decks of cards).
  • Basic strategy with a cut card – this result refers to the strategy of play which includes a cut card and is based on total dependent basic strategy. This card tells the dealer at which point does he have to shuffle the cards.
  • Basic strategy with continuous shuffler – the cards are shuffled after every hand and the play is based on total dependent basic strategy.

House edge vs card counting

Blackjack conquered casinos almost immediately when it appeared in them. Simple rules, frequent winnings – what more do you need? A strategy! Around 1950s first studies had been conducted to find out how to decrease the casino’s house edge and how to increase the chances of winning.

The studies were based on a computer-calculated strategy of the basic game, levelling the casino advantage. However, only a decade later, thanks to Edward Thorp, the so-called card counting has revolutionized the concept of blackjack and has allowed many talented players or teams of players to get some nice winnings.

What is this method all about?

Well, Thorp discovered that the advantage of the casino over the player increases or decreases along with the cards distributed. The basic theory is that the higher cards are dealt, the more advantage the player has.

Thorp divided the cards in the deck into three groups: high, neutral and low. The group of high cards is 10, J, Q, K and A, neutral is 7, 8 and 9 and the low ones are the remaining, that is: 2,3,4,5 and 6.

Cards of each group have been equipped with the value: high is -1, neutral is 0 and low is +1. Counting these values for the cards dealt out, the player knew that if the result is above zero, then it means that there are more high cards left to be dealt out and one should hit.

Online casinos use several decks to play blackjack at the same time. So in order to get a real value while counting cards in blackjack, the current value should be divided by the number of decks in the casino shoe.

And so, if the current value obtained during card counting is +8, then if 4 decks take part in the game, the real value will be +2. Of course, it’s better when a high value is combined with a small number of remaining cards to be dealt. If that’s the case, player’s advantage over the casino increases.

However, online casinos are trying to discourage players from using this technique. One of the ways is as mentioned using multiple decks of cards. The other is using a cut card which tells the dealer to shuffle the cards.


blackjack and chipsPlayers tend to underestimate the importance of the house edge. Many of them think that it’s really not that important as it doesn’t play a crucial role. However, that is a big mistake.

As you can learn from this article, a lower house edge gives the player a bigger chance of winning. If the house edge is high, players are going to lose their money more quickly. The outcome would be that they won’t be able to stay in the game long enough to make a profit.

Blackjack is a casino game with a relatively low house edge when compared to other casino games. This is why it gained such a big popularity and is played in casinos around the world.

Just remember, blackjack having a low house edge is not everything. It’s not going to guarantee you an easy win. You also need to have a strategy, knowledge and skill set to be able of putting yourself at a chance of winning.

Always make sure you know the rules of the game and have your strategy figured out!

We wish you good luck!