Number Of Decks In Blackjack

To calculate our True Count, we simply divide our Running Count by the number of decks left to be dealt. In a standard 6 deck blackjack game each true count will move the house edge half a percent toward the player’s advantage. So a true 1 would basically erase the house edge and blackjack would be an even game. 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%.

Blackjack odds are percentage figures which represent your probability of losing or winning a hand. They can also represent the house edge or their profit margins as well. Usually probability odds don't mean much on the short term, but they clearly average out in the long term and this is why the casinos always win over the long term.

We decided to make a few tables and charts of the most common blackjack probability odds for various scenarios and situations found while playing blackjack. The most important odds percentage represents the dealer's edge in the game. This is the long term advantage that they have which will eventually take your money away. Blackjack is actually one of the most popular games in the casino and also has some of the lowest odds of all the casino games, except casino craps of course. Generally their edge ranges from 1% to 15% depending on what variation of blackjack you are playing.

How to Beat the Casino House Odds

There is one feature that makes blackjack more desirable than any other casino game. There is actually a way to beat the house edge by increasing your odds. In fact, your probability odds in blackjack can be increase to the point where you would actually be making the profit in the long term, essentially turning the casino into a personal ATM. This practice is known as card counting and casinos don't like this because they know they will be losing money.

Before you start card counting, you should learn 'blackjack basic strategy', which is the mathematically correct way to play every move in blackjack to get the best odds. This can lower the house edge to less than 1 percent. When that percentage goes to a negative number such as -1%, then it is you who has the edge over the casino. This is when you complement basic strategy with card counting to get the highest efficiencies.

Odds vs. Dealer Up Card

The first odds chart shows what kind of advantage the player has vs. the dealer based on what his up card is showing. The first column in the chart is what card the dealer has showing after the cards have been dealt. The second column of the table shows the dealer's probability of going bust based on each card. The last column shows the advantage the player has and the probability of winning based on the basic strategy theory. As you can see, the dealer has about a 43% chance of going bust when he has a 5 showing as an up card. At the same time, the player has about 23% advantage as well. Notice that the player advantage goes negative when the 10 cards and ace start showing up. This means the player is more likely to lose.

Blackjack odds of Busting While Taking a Hit

This chart shows the probabilities of going bust after taking a hit. Busting means that your card total would go over 21 points and would be a hard total as well. The highest score you can get when being initially dealt two cards is 21 points so you can never go bust. This means if you took a hit on a hard 21, you would have a 100% probablity of going bust, which is common sense. Also, if you have 11 points or less, it is impossible to go over 21 points on the next hit and your odds of going bust would be 0 percent.

House Advantage with Multiple Number of Decks

The number of 52 card decks in a game of blackjack influences the house edge. In some cases, the odds increase in favor of the casino when more decks are used. The advantage edge can be as much as 1% towards the casino and this is a big number in terms of odds over the long term. As you can see here, a single deck of card gives the lowest edge for the casino and gives the player better odds. Multiple decks such as eight decks increases the house edge almost 18 times more than it would for the single deck!

Two Card Frequency Odds

The next odds table deals with the first two cards being dealt or the 2 card frequency odds. Every player is dealt two cards at the beginning of a round of blackjack so this chart tells you the percentage of getting different categories of hands. A natural blackjack is only 4.8%, which essentially is an ace dealt with a ten card straight off the initial deal. Normally the odds are 3 to 2 and you would win $3 for every $2 wagered. It's a small percentage but it's the most desirable hand to get. The lowest hand you can get is two points (two aces). This is part of the decision hands group where players are usually dealt soft hands and can make decisions without going bust. This group is the most common.

The other category is the hard standing hands. These hands are somewhat desirable because of the high scores likely to beat the dealer. These are the second most frequent two card blackjack hands. Finally there is a no bust two card hand. No bust means any two card hand that won't bust on the next hit, such as any soft hand or hard hand that is 11 points or less.

Probability Edge for Each Card Removed from Deck

The next table shows how much your odds improve after when certain cards have been dealt and removed from the deck. Certain cards taken out of the deck and increase or decrease your blackjack odds percentage and the house edge.

This is very important for card counting. If you want the absolute perfect odds in card counting, you have to acount for each small change in the odds whenever a card is dealt. As you can see from the table, when small cards are taken out of play, the odds increase in your favor overall. This is a paramount property of card counting. The opposite happens when large cards are dealt. Your odds begin to decrease. When you are counting cards, you will notice your count decreasing when large cards are dealt.

You can imagine how complicated it would be to be adding these numbers in your head while card counting at the same time. If your mind was a computer, it would be easier to keep track of the percentage. Some people can do this, and this is the way to become a perfect card counter! It is easier to keep track of the odds when playing with a single blackjack deck. For example, when five cards are seen on the table, they offer a 0.67% increase in your advantage. In fact, when a lot of fives are used up, your odds will be much higher than if any of the other low cards were used up, even the six point cards. Also, these effects are cumulative so you always need to keep track of the odds after every card is dealt. This data is actually quite amazing!

Dealer Final Hand Probability Odds

This next table shows the odds of what the dealer's final hand will be. Usually in blackjack, the dealer must hit on 16 and stand on 17. These rules are slightly different for other variations of twenty-one. So generally, the odds of the dealer's final score being 16 are 0% because he must hit. This table will show the probability of the dealer busting or getting a non-bust hand as well as natural blackjacks.

Blackjack is one of the most popular games in any casino, whether you are playing at an online casino or in the real world. However you play blackjack, there are lots of minor gameplay differences that can have a significant impact on the return to player (RTP) rate and the number of decks used is one of the easiest to understand.

The RTP essentially details how much a player can expect to lose on average when they play a given casino game. All casino games have a profit margin built into them which is how the casino makes money. The RTP is expressed as a percentage and can vary quite significantly. When talking about slots and related games, the UK Gambling Commission states that, “There is no statutory minimum percentage payout for a gaming machine.” On slots you may find an RTP of as little as 80%, meaning that for every £1 staked, a player can expect to get back just 80p in the long term.

This is just an average though and is typically calculated on 100,000 spins or more when it comes to games that are entirely random. Other casino games, including roulette and blackjack (and others) have a fixed RTP that is based on the maths that underlie the game.

For example, in roulette because there are 37 slots on a standard UK wheel and any given number returns 35/1, we can say that in theory if you place 37 single bets of £1 on a single number, you would expect one to win, meaning you have £36 left having started with £37. This is an RTP rate of 97.3% and indeed this is the RTP of roulette, equating to a house edge, or casino profit margin, of 2.7%.

Optimal Play

When it comes to blackjack, complex mathematical calculations and a deep understanding of the game have led to the creation of the concept of optimal play. This means that based on the player’s card and the dealer’s card, there is always a single course of action that delivers the most favourable results for the player in the long term.

The RTP in blackjack is based on a player using optimal play and any deviation from this will decrease the RTP, leading to larger losses for the player and bigger profits for the house. Assuming optimal play, the RTP in blackjack then depends on the exact rules being used and there are many factors that can have an impact on this.

In general, most online casinos offer blackjack that has a house edge of between 0.4% and 1.5%, though it can go a little lower under the most liberal rules or a lot higher with some less generous casinos that stack all the rules in their favour. The number of decks used has a big impact on the house edge and some of the other factors include:

• Dealer hits or stands on soft 17 – if hits, this reduces the RTP
• Player allowed to double after a split – if yes, this increases the RTP
• Player can double on any first cards – if so this also increases the RTP
• Split aces – if the player can split aces the RTP is better
• Blackjack pays 6/5 not 3/2 – rare these days but lower BJ odds reduces the RTP by a huge amount

How Big Is The Impact Of Multiple Decks?

The impact of more decks is quite significant, perhaps much more so that many players might realise. If we assume fairly standard, but still rather liberal, rules in the other areas that matter, including those listed above and others, we can see the impact of adding more decks below. Note that this table shows the house edge, which is the casino’s profit, rather than the RTP. Whilst a high RTP is a good thing, anyone playing blackjack wants the house edge to be as low as possible.

Number Of Decks In Blackjack Real Money

Whilst this may not seem like a big deal, even small percentage differences add up over a long period. Clearly the biggest jump is when moving from a single deck to a double deck game, the house edge is not too far off quadrupling. Blackjack is a game where players may play hundreds or even thousands of hands and even with small stakes, such differences soon add up.

If you are playing blackjack in order to complete the bonus wagering requirements of an offer then this will be of particular interest. The RTP with blackjack is better than almost any other game going (video poker can beat it depending what rule variations are being used in both games). Because of this it is a popular choice for those playing with bonus funds who want to try and make sure they still have some “free” cash left when they have finished the wagering.

Some years ago now most online casinos realised this and that is why many exclude blackjack from bonus wagering or allow it only to contribute at a reduced rate, where perhaps a £10 stake reduces the rollover by just £1. None the less, whether you are trying to clear a bonus or simply playing for fun, opting for the blackjack variation with the fewest decks in play is the best bet, all other rules being equal.

Many online casinos offer a wide range of blackjack games and variants, with ever more new and novelty iterations of this classic game available. In general though, whilst the chance to win larger amounts or shiny add-ons can grab your attention, more often than not it is the simplest forms of the game that have the best RTP. Not all sites offer single deck blackjack, but if they do this should almost certainly be the game to plump for.

Why Does More Decks Spell Bad News For The Player?

Number Of Decks In Blackjack Simulator

So, we have established that playing blackjack with multiple decks will negatively impact your long term results but why is that the case? Well, it is a combination of a number of factors, one of which and perhaps the most important, is the increased chance of obtaining a blackjack.

Let us assume you get an ace first card in a single hand game. Your chance of getting blackjack is 16/51 (there are 16 face cards or 10s out of the 51 remaining cards), or 31.373%. In a two-deck game that becomes 32/103, which is 31.068%. This only seems like a small difference but it has a notable impact and whilst the same applies to the dealer’s chance of getting blackjack, whilst you will be paid at 3/2 odds, they will receive just your stake. What’s more, the chances of a blackjack push (where both you and the dealer get a blackjack) are considerably reduced.

Similar maths and theory applies to other potentially profitable situations for the player, such as when holding a good two-card combination such as a 7 and 4 or 6 and 5 that can be doubled. And going back to blackjack, just as the player has a better chance of hitting a natural from an ace, the same is true if their first card is a 10.

Of course though, as we said, the single deck advantage is only necessarily true where all the other rules are the same. Some casinos, both online and offline, offer a reduced payout of 6/5 for blackjack in their single deck games. Let us now add a third column to our previous table in order to show how just with that seemingly minor tweak, the house edge goes up and the RTP goes down.

The table shows that the impact of reduced blackjack odds is much greater than increasing the number of decks. So whilst you may hear “always play single deck” as advice, it is crucial to ensure that the other key rules are also the same.

Playing a single deck game with a reduced 6/5 blackjack payout has a house edge roughly two and a half times that of an eight-deck game with the normal 3/2 odds. So, whilst playing a game with as few decks as possible is great, it is far from the only factor to think about.

Reduced Decks And Card Counting

Number Of Decks In Blackjack Tournaments

Card counting is easier and more effective the fewer decks that there are. The vast majority of players will not be using this technique, which we look at more closely in a separate article. However, making things harder for those that do count cards is a fairly significant impact of using multiple decks and part of the reason casinos introduced multideck games.