Card Counting In Blackjack

Learn how to count cards in Blackjack to increase your edge over the house. Understand the various blackjack card counting systems.

Card counting in blackjack is a much-discussed and often, debated topic. Here, we attempt to throw light on everything about this interesting technique, right from how it started to the ways of card counting and also, how casinos try to prevent players from using card counting in a game of blackjack being played in the casino.

What is Card Counting

Card counting is a math-based strategy used in blackjack to determine whether the next hand will be of probable advantage to the player or the dealer. The aim and intention of the card counters are to keep a count of the high and low-value cards as can be seen in the game and thereby, try to minimize the house edge of the casino. As card counting enables the players to get an idea of the composition of the remaining cards that are yet to be dealt and played, they are able to make better decisions and minimize losses.

The technique of card counting is also referred to as card reading when used in trick-taking games like spades and contract bridge. Card counting also may be useful in certain poker variants.

How Card Counting Works

Blackjack card counting is a strategic process that works by keeping a running count. The basic card counting system assigns a positive, negative, and zero value to each card. The point values that are assigned to the cards should correlate to the individual card's Effect of Removal (EOR). EOR is basically the estimated effect of removing a particular card from the game and how it affects the house edge percentage.

When a card of a certain value is dealt with, the count is adjusted by means of the card's counting value. Accordingly, low cards increase the percentage of the high cards in the remaining set of cards and thereby, increase the count also. The high cards, on the other hand, decrease the count for just the exact opposite reason. As an example, the Hi-Lo card counting system subtracts 1 for each dealt 10. King, Queen, Jack, and Ace and adds 1 for any values between 2 and 6. The values 7 to 9 do not affect the count because they are assigned a value of 0.

The bit of information that the player gets access to by counting cards lets him understand when to bet big and when to bet small. Generally, having more low-numbered cards in the deck is bad because it means the player is unlikely to get a blackjack on the first two cards and that the dealer is more likely to bust.

Card Counting Blackjack Definition
Card Counting Blackjack Definition

How To Count Cards in Blackjack

Card counting in blackjack can be done by players using the following 3 easy steps:

  1. First, each card should be assigned a value, according to the plus-minus count. Cards 2 to 6 have a +1 count, cards 7 to 9 have a 0 or neutral count, and cards 10 through Ace have a -1 count.
  2. The counting starts at 0. Players will add the card's value to the count as each card is dealt. For example, if an Ace, King, 2, 7, 6, 4, and 5 are dealt, the count is +2, based on the values of the cards. The dealer's face-down card is not counted until flipped.
  3. The counting continues as cards are being dealt out of the deck. Betting decisions are taken based on the count. Ideally, a player should bet higher if the count is negative and lower if it is positive.

Using the very same steps, card counting can be done in the same way in online blackjack. Players would start counting after the cards are shuffled and dealt. After a given round, when the running count is positive and the undealt cards are mostly high cards, the players must increase the bet. When the opposite is the scenario, decreasing the bet is the way to go.

Card Counting Systems in Blackjack

There are a few distinctive card counting systems that blackjack players adhere to. Some of these are simple and straightforward while others are more advanced.

Hi-Lo System (Basic Card Counting Strategy)

The is the most basic card counting strategy, based on Edward Thorp's ten-Count. The system is relatively simple and useful for beginner blackjack players. In the Hi-Lo Card Counting System:

  • +1 value is assigned to cards from 2 to 6 as these are low cards,
  • the 7, 8, and 9 cards are given the value of 0,
  • while the Ace, King, Queen, and Jack have a value of -1.

The counting starts with the first dealt card from the deck. Based on the card numbers and values, the higher the positive number in the player's count, the more high-value cards are remaining in the deck and vice versa. Players usually begin with a running count of 0 when the cards are first dealt with and proceed by dividing the number by the number of decks in the shoe.

It is advisable for card counters to begin practicing with one deck before moving on to the other complex systems. One or two decks work for card counting. Card counting practitioners also try to keep the running count accurate with added disturbances like the radio and TV playing simultaneously.

Hi-Lo System (Blackjack Card Counting)
Hi-Lo System (Blackjack Card Counting)

Omega II System

The Omega II system is an intermediate level system of card counting, developed by Bruce Carlson. It is also a multi-level system where some cards are counted as two-point and some others are counted as one-point. Accordingly, cards 2, 3, and 7 have a value of +1 while the low cards like 4, 5, and 6 are +2. The 9 is equal to -1 while the 10 and the face cards King, Queen, Jack are marked with -2. The Aces and the eights are counted as 0. 

This is a balanced card counting system, which implies that the player will arrive at 0 when all the cards have been dealt, if he has been able to keep track in the right way.

Hi-Opt I & II Systems

The Hi-Opt systems give two options, the Hi-Opt I and Hi-Opt II. Let's discuss these separately. In Hi-Opt I:

  • the 3, 4, 5, and 6 cards are assigned with +1 value,
  • the King, Queen, Jack, and Tens are -1, and
  • the Ace, 2, 7, 8, or 9 are given 0.

It is a balanced system like the Hi-Lo system and players need to keep a running count to be able to make informed betting decisions.

The Hi-Opt II is also a balanced system with different values assigned to each card.

The +1 value is given to 2, 3, 6, or 7. Then, the players need to add 2 to their running count when they see cards 4 and 5. With 10 and the face cards, players need to subtract 2 from the running count. For an Ace, 8 or 9, the value is 0.

Wong Halves System

The Wong Halves System is the most elaborate, three-level card counting system, developed by . Like the Omega II, this also is a balanced system. Once all cards in the deck have been dealt with, the final result of your calculations should amount to zero. Players are advised to calculate their true counts after each deck has been dealt.

The values assigned to the cards in the Wong system are:

  • 10's, Jacks, Kings, Queens, and Aces are given a value of -1;
  • 8's are valued -1/2,
  • 9's have the neutral value of 0;,
  • 5's are 1 ½,
  • 3's, 4's and 6's are valued 1, and
  • 2's and 7's are given the value of ½.

To avoid fractions, players can double the values of ½.

Again the running count should be converted to a true count to determine the odds of winning. It would be a good idea to calculate the final count after each deck is dealt with. This is easier than calculating a final count, based on several dealt decks of cards.

Wong Halves System (Blackjack Card Counting)
Wong Halves System (Blackjack Card Counting)

Red 7 System

The Red 7 system of counting cards in blackjack is simple and easy for beginners as it is a one-level system. The system is built on the principle of high vs. low cards. The higher value cards are assigned a value of -1 while the lower value cards are marked as +1. The neutral 8's and 9's are marked by a 0. With respect to the 7's in this system, color plays an important role too. If the 7 is red, it is a low-value card (+1), if the 7 is black, it is considered neutral and assigned a 0. The higher the final count, the better it is for the players.

KO System

Popularly known as the KO system, the Knock-Out system of card counting in blackjack is suitable for both beginners as well as intermediate players. The system was first introduced by Fuchs and Vancura in a book, called .

Similar to the Hi-Lo method, Tens, Aces, Queens, Jacks, and King go by the value of -1, while those from 2 to 7 are assigned a +1. 8's and 9's on the other hand are marked as 0 here. The system is obviously not balanced as in the end after all cards have been dealt, the final count will not amount to a 0.

Zen Count

The Zen Count system is another balanced system where the count comes down to 0 after all the cards have been dealt. This is also one of the basic and simpler systems and the cards are valued in the following manner:

  • 2, 3, 7 = +1
  • 4, 5, 6 = +2
  • 8, 9 = 0
  • 10, Jack, Queen, King = -2
  • Ace = -1

When the player's true count is at 0 or less, he will be placing the minimum bet, and the idea is to increase your bets by 1 unit, or minimum bet, each time the count goes up. This steady increase is designed to not catch the attention of the casino, although players need to be aware too.

Team Card Counting

The card counting system was largely based on the Hi-Lo system and the same values were assigned to the cards. So, high cards were -1, low cards, +1, and the rest, 0. Alongside this technique, the team used the strategy of a three-person team with:

  1. a big player,
  2. a controller, and
  3. a spotter.

The spotter would be the one to keep the count and when verified, they would signal the big player to place the bet. The team was highly successful in beating several casinos and making millions of dollars within a small span of time.

Quick Explainer On The Basic Blackjack Card Counting Strategy.

Card Counting Apps

It might be easy to explain blackjack card counting as a technique but it is a difficult skill to learn and master. Card counting not only requires the players to have the ability to memorize but also possess a mathematical bent of mind and process numbers in their minds really fast. To make the task easier, however, there is blackjack training software you can use to learn the technique of card counting.

is an app-based game that shows real blackjack card counting techniques and can teach the players rather effectively. is another app that blackjack players simply love. There is also another iPhone card-counting app called 'A Blackjack Card Counter' and it helps players in determining the optimal times to bet in the game.

There are a few gadgets also that can help players in the process of card counting while playing blackjack at a casino. However, these apps and gadgets are good for learning the skill and not using in a real casino where the use of these aids are banned.

Is Card Counting Illegal?

Card counting is not illegal in the US, nor is it so under British law. However, the use of any external card counting device or person that assists the player in counting cards is strictly prohibited by the casinos. In fact, casinos, in general, object to the practice of card counting and try to prevent it. They do keep a watch on the suspected card counters and often ban them from playing in the casinos.

Although many casinos are legally not allowed to ban the players as such, a few, especially in Nevada are strictly against the use of card counting apps and devices. The reason is card counters can actually lower the house edge to a significant extent and make the casino lose money.

Card Counting Countermeasures

Casinos in the US are evidently against the practice of card counting. To prevent card counting and detect card counters, the authorities take certain countermeasures, some of which are explained below.

Multiple Decks of Cards

Apparently, card counting is difficult in a six or eight-deck game as compared to a single-deck blackjack game. The more the number of cards, the greater is the difficulty in keeping track of the count. That is why; casinos prefer multiple decks of cards in the games to prevent card counting as much as possible.

Continuous Shuffling Machines

The use of Continuous Shuffling Machines (CSM) is a very significant countermeasure against card counting. In this, the dealer puts the already dealt cards back into the machine for reshuffling. The dealer basically puts back in and takes out the cards from the machine almost continuously leading to such shuffling of the cards that would make card counting extremely difficult.

Banning Winners

This is a very blatant countermeasure that casinos often take against the card counters. Although it is illegal to ban any player from playing in a casino unless he has violated any rule, some casinos prohibit the winners of large sums of money in blackjack, from entering the casino premises again. This is based on the assumption that the subsequent winnings are results of card counting techniques being used by the particular player.

In addition to these measures, many casinos have security staffs closely watching over the players and reporting any noteworthy behavior such as a dramatic variation in the bets placed and so on.

Card Counting Countermeasures in Blackjack
Card Counting Countermeasures in Blackjack

History of Card Counting in Blackjack

Blackjack card counting has an interesting history. , the American mathematician is known as the Father of Card Counting. In his book, "", published in 1962, he wrote about the optimal playing and betting strategies for effective blackjack. The techniques he mentioned, however, are no longer applicable. Also, the 10-count system was harder and less profitable to use compared to the point-count systems that have developed since.

Even before the publication of Edward O. Thorp's book, a few professional card counters were beating the blackjack game in some Las Vegas casinos. Al Francesco was one of the earliest card counters who had been hugely successful in beating the casinos. Francesco was also the one who taught the famous Ken Uston, the technique of card counting. Now, Ken Uston was a part of the 'Big Player' team of AI Francesco. He was also the first to write about the tactic of card counting, as it is practiced today.

The Big Player blackjack team consisted of card counters, referred to as spotters. They were spread around the tables in a casino, keeping track of the count and signaling the big player when the count indicated a player's advantage. Then, the big player joined the game at the table, placing the maximum bet. Similarly, when the spotter indicated that the count has dropped, this would signal the big player to leave the table. This way, the team avoided disadvantage plays and at the same time, appeared so random that the casinos could not detect them. The interesting part was that the spotters who did the actual counting never changed their bet size or strategy and remained inconspicuous thereby.

Famous card counters in the history of blackjack are recognized and featured by the , housed at the Barona Casino, in San Diego, California.

Blackjack Card Counting: FAQ

Answers to the most common questions about card counting in blackjack.

Is blackjack card counting still possible?

Blackjack card counting is possible. However, these days, casinos take several countermeasures to stop the practice. These include using multiple decks of cards, CSMs and even banning winners of large sums from playing in the casino.

Does card counting work in online blackjack?

Yes, card counting works in online blackjack too. But, some online casinos use software that shuffles the cards after each hand, making card counting highly difficult.

Is counting cards in blackjack illegal?

No, card counting in blackjack is not illegal in the US. But using of any person or device that assists the player in counting cards is strictly prohibited by the casinos.

How to practice card counting?

Card counting is practiced by a mathematical method of assigning values to each of the cards and then, keeping a track of the count, based on the dealt cards.

How do casinos prevent card counting?

Casinos prevent card counting by several measures like shuffling techniques, CSMs and security measures to keep a watch on unusual betting patterns and variations in them.

How much money did the MIT card counting team make?

The MIT blackjack team made millions, close to $57.6 million, as a whole.

What is the list casinos use to share card counting information?

Casinos can detect card counters through computer programs and tell if the players are counting cards. They can also get information on the system the players are using.

How much money can you make with card counting?

Card counting might not be hugely profitable always. However, in the long run, players using the technique can be expected to win 1% of the total sum of his action. This comes down to about $19 an hour if he plays 75 hands with an average bet of $25.

How to simply count cards in blackjack?

The card counting process involves assigning a value to each card like +1, -1 and zero. Based on these values, players need to keep a running count of the cards as they are being dealt. Bets are placed accordingly, along the course of the game.

What is the hi-lo system in blackjack?

The Hi-Lo count system in blackjack is a simple way of keeping track of the high cards left in the deck. The system is called the balanced system because on counting every card in deck, the balance would be 0. The values given to the cards in this system are +1 for 2-6, -1 for 10-Ace and 0 for 7-9.

When to bet in blackjack when counting cards?

As a general rule, a player should increase the bet when the running count is positive and the undealt cards are mostly high cards. The player should decrease the bet size when the running count is negative and the undealt cards are low-card heavy.

The entirety of this guide was a counting cards for dummies, but also went beyond with some advanced techniques and tips. Card counting is an undoubtedly helpful skill for blackjack players but it is difficult to practice because of the restrictions that the casinos put in place. It is, however, a blackjack playing skill that players must learn using the popular apps out there, though such helpful devices should never be taken to the casinos.