Blackjack Card Counting

Card counting is a game strategy used to track the ratio of high cards to the ratio of low cards in blackjack. Card counting is a statistical method to get an advantage over the casino while sitting at a blackjack table. The reason for counting cards in blackjack is based on the fact that a deck of cards with more high cards (tens and aces) is better for the player than a deck of cards with low cards, while a deck with low cards is better for the dealer.

A deck which possesses more aces and tens increases the player's odds on getting a blackjack, and this type of hand pays out more than other hands. The dealer, on the other hand, is more likely to bust a stiff. Card counters use their methods to decide when to raise their bets – when the ratio of high cards is larger than low cards.

Blackjack Card Counting

History of Card Counting

The official birth of card counting was with the publication of Dr. Edward O. Thorpe's book “Beat the Dealer” in 1962. This book was a hand-book for those blackjack players who were seeking betting and playing strategy tips. The book's theories are totally mathematically sound, but many cannot be applied today because the casinos have since taken counter-measures to fight the phenomenon.

Thorpe's book, however, was not the first documentation of blackjack card counting methods, as there existed a trend of card counting before its publication. In the 1950s and 1960s a small group of professional card counters were making their rounds in Las Vegas casinos and beating the establishments. Jess Marcum is thought by some as having developed the first proper point-count system. Other notorious names in card-counting circles were Joe Bernstein and The Four Horsemen (Roger Baldwin, Wilbert Cantey, Herbert Maisel, and James McDermott). The Four Horsemen published a very accurate blackjack card counting system which required the use of adding machines.

Big Player Team Strategy

In the 1970s, top blackjack player Ken Uston, wrote about a tactic of card counting which he titled Big Player Team. In Uston's system, a team of card counters are required (called spotters) and each one has the responsibility of manning a casino table and keeping track of the count. The spotter has to signal to the big player when the table's count becomes advantageous and the big player then joins the table and begins to place maximum bets. When the spotter sees that the count is once again low, he signals for the big player to leave and to move to the next advantageous table. This system allowed the big player to avoid wasting time playing at non-advantageous tables and also avoided detection by the casino authorities, because he would play at random tables.

Legalities of Card Counting

In theory, as long as a counter only uses his brain and not a mechanical device to count the cards, there is nothing illegal about tracking the contents of the deck of cards. In practice, however, because most casinos in Nevada are on private land, the casino has the right to remove anyone suspected of card counting on their premises. If a player insists on returning, once being thrown out of the casino, he can then be arrested for trespassing. Legally, this does not constitute a form of discrimination because card counters do not fall under any classification of people covered by discrimination laws. In Atlantic City, the law states that card counting is allowed, but once again, in practice, casinos have made it nearly impossible.

Choosing a System

There are over 100 card counting systems published and many websites sell blackjack simulation software with which you can try out the system. The simpler systems are obviously easier to learn and are what most counters begin with. The more complex systems are in theory more profitable per hour, but they are generally accompanied with a higher rate of error due to the need for high concentration over an extended period of time.

The first counting systems which were developed in the 1960s and 1970s were geared towards a single deck, which was the most popular form of play at the time. Nowadays, however, most dealers play with a multi-deck shoe and systems have been developed to take these into account. Experienced counters will switch from one system to another depending on the dealer's shoe.

Hi-Lo System

The Hi-Lo system is one of the easiest and most popular blackjack card counting system. The system assigns specific point values to every card dealt to the player. Aces and ten point cards are worth -1; 7,8 and 9s are worth 0 and 2,3,4,5 and 6s are worth +1. Using this system, a counter must basically add and subtract the number 1 in order to keep a count of the deck. The player assigns a point to every card dealt – as well as to the dealer. The counter makes wagering decisions depending on the deck's current count.

The higher the plus-count (the higher the number of tens remaining in the dealer's pack) means that the player has an advantage and he should increase his wager. If the running count is zero, neither a player nor the dealer has an advantage. When the minus count is high, the player is at a disadvantage and should therefore decrease their wager.

As more and more cards are dealt, the probability of accuracy increases and a player can therefore increase his wager significantly when the count is in the plus. A player's primary moves should always be according to a basic strategy learnt prior to card counting. The basic strategy's rules should come before the card counting system but can be adjusted accordingly depending on the count.

In single deck games, if a point count is +2 or more, then a player should increase their bet. In multiple deck games, the wager should be increased when the true count is +2 or more. The difference between a single deck count and the true count in a multiple deck game is that the true count is based on the actual number of decks still to be played. The true count is determined by dividing the running count by the remaining number of decks.

The Hi-Lo system is one of the easiest systems to use, and if used correctly, provides top results.

Hi Opt 1 System

Hi-Opt 1 is a more complex system than Hi-Lo and is considered advanced. With Hi Opt 1, cards 3-6 are counted as +1 and all the 10 value cards are counted as -1. The cards in between and the aces are all counted as zero. This system also keeps a side count of aces by watching how many aces have come out in each quarter deck and mentally adjusting the count up or down. The aces are only counted for wagering purposes. While this may be a more accurate way to keep count, beginners will find it confusing keeping track of two separate counts.

Casual Card Counting System

Casual card counting is a very informal system which does not require much mathematical or concentration skills. A casual card counter simply needs to monitor the general flow of cards coming out of the deck. For example if a counter see that for a few hands not many picture cards have been dealt, they can assume that the probability of a picture card being dealt in the next few hands is high – thus increases their bet. The key to casual card counting is spotting extreme trends. A casual counter can easily tell if there has been a prolonged absence of a certain type of card and will therefore adjust their wagers accordingly.

Cluster Card Counting System

Cluster card counting is another system used in order to track the ratio of high cards being dealt. This system is based on the assumption that cards tend to ‘cluster' in specific parts of the multi-deck shoe. A cluster card counter will track the shuffling of the cards at the end of the shoe and can try and determine which section of the shoe will be full of high cards.

A cluster card counter needs to make note of the flow of the cards when a new shoe is played and then has to mentally divide the pile into sections equal to one deck. The deck needs to be tracked for which portions of each section possess many aces and ten-point cards. Each section must then be rated as being rich or poor in high cards. The counter must then remember how many cards were placed in the discard box. At the end of each shoe, the dealer's shuffling pattern needs to be watched in order to track where the clusters of good cards are situated and where they will be dealt in the next shoe. According to the clusters of good or bad cards, the counter will increase and decrease his wager.

Cluster card counting is one of the harder systems to master and casinos have also taken several counter measures against this system which makes it even harder to apply. Those tables that use automated shuffling machines or two discard racks are not welcome venues for cluster card counters.

Evaluating the Effectiveness of a System

There are three parameters which can be used to evaluate the effectiveness of a counting system – betting correlation, playing efficiency and insurance correlation. Betting correlation is correlation between card point values and effectiveness of card removal. This parameter will indicate how well a card counting system forecasts a good betting climate and is quite important in six to eight deck games. Playing efficiency will help a player determine how well a card counting system handles fluctuations in playing strategy and is most effective in one and two deck games. Insurance correlation is the ratio between card point values and the value of cards when ‘insurance' is applied in the game.

Tips for Card Counting

*** Learning a basic blackjack strategy is the most important step in card counting. The truth is that there is nothing really to learn, only memorize and with practice, the basic strategy will become a player's second nature.

*** Becoming fast at the counting strategy chosen is essential in maintaining a flowing counting pace. Using the hi-lo system as an example, a player should practice on a deck of cards outside of a casino to ensure that every time, the count ends up at zero. The optimal time for counting an entire deck is 30 seconds, and once this has been mastered, a player can move onto flipping to cards at a time and seeing how fast they can count. Learning to ignore cards that cancel out each other is a useful trick.

*** Once the running count has been perfected, a player needs to convert the practice count into the real thing – the true count. This is imperative in order to know what a player's edge is and to bet accordingly. The running count is divided by the amount of invisible decks. This should ideally be done in one's head but a player can also use chips to keep track.

*** A seasoned card counter will be able to count cards even while being distracted. A casino by nature is a noisy, busy, hubbing place and a player needs to practice counting and concentrating in a distractive environment. This can be done at home while talking on the phone, listening to music or while watching television.

*** Knowing how to spread one's bets will determine whether a counter come out advantageously or not. Making money from the blackjack table requires a player to bet more on hands when the table has an edge and less when the dealer has an edge. There is an essential balance in playing a bet spread that is to a player's advantage on the one hand, but which will not attract the casino's attention, on the other hand.

*** Some casinos take counter measures against counters by only dealing a few of the shuffled decks. If a player sees that the conditions for card counting and betting accordingly are not suitable, then they should avoid these tables. Due to the very small profit margin gained from card counting, it is not advisable to count and bet at tables when even the slightest variable is off.

*** Maintaining a realistic bankroll is an important tool for a card counter, in order to avoid the possibility of not surviving the table. High bankroll fluctuations are common for a card counter and this fact should be taken into account when planning the size of a bankroll.

Casino Counter Measures

Just as card counting systems have developed and become more sophisticated over the years, so have the counter measures taken by casino operators. In the hey-day of card counting, teams of professional counters would swarm on casinos and would break their blackjack banks and walk off with millions. This exciting trend resulted in the publication of many books about different card counting systems, but the casinos began fighting back just as hard. Today several sophisticated counter measures are practices at most casinos:

*** Using multiple decks increases the starting advantage of the casino and decreases the movement of percentage advantage witnessed throughout the shoe.

*** Decreasing deck penetration before shuffling stops the flow of information about deck composition reaching the counter.

*** Restricting the bet size to the table minimum if a player joins a blackjack game after the first few rounds have been dealt. This move stops card counters from only joining in when the table is advantageous and forces the player to play all hands of the shoe.

*** Restricting the number of boxes a player is allowed to play decreases the potential that the card counter possesses when betting in positive situations to one or two boxes of the table's maximum allowance.

*** Barring suspected card counters from the premises greatly reduces the casino's risk.

*** Reshuffling the deck when a player begins to significantly increase his bet, which puts the deck back into the casino's favor.

*** Automated shuffling machines allow for the shoe to be reshuffled after every round, therefore reducing the ability to track cards.

*** High technological surveillance systems allow the casinos to monitor the movements of all players. Every player entering the casino is identified and if the player has a record or suspicion of being a card counter, he can be asked to leave.

*** Card counter spotters placed around the blackjack tables and casino floor are trained in identifying the trends and characteristics of card counters and when suspicious, they alert the casino authorities.

*** Taking the liberty to change house rules for blackjack can throw the card counter off track and in turn can cause him to loose his slight advantage.


While almost every aspect of land blackjack can be mirrored in the online version, one thing that cannot be applied to online blackjack is card counting. In online blackjack the cards are totally random, the shuffling cannot be monitored one's computer screen and with random number generators, the cards cannot be predicted. Online casinos might not have the surveillance technology and the ability to physically stop a player from counting cards, but in practice it is not possible to do.

Most online casinos shuffle the cards after every hand. Even if only one deck is played with, which is often not the case, when then casino shuffles after every hand, even the most technological-savvy card counter who MIGHT have mastered some sort of card counting technique, will loose the advantage.

The best system to stick with for online blackjack is a basic strategy. Card counting will not pay off in the virtual casino world. Learning a good basic strategy and sticking to that is probably the cleverest move an online player can make.

Posted by Nick David

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