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Blackjack Card Counting

Card Counting in Blackjack

Card counting is a strategy for playing blackjack that can potentially give players an advantage in the game. A few different card-counting strategies exist, and while most of them are relatively simple to learn, they take a lot of time to master.

Whether you’re completely new to card counting, curious to learn more, or want to brush up on your card counting skills, this guide will cover it all. Our team of casino experts have compiled all the information you need to know about what is card counting, how it works, and when you should or shouldn’t use it.

We’ll also settle common questions like, ‘Is card counting illegal?’ and ‘Does card counting work?’ and for if you’re interested in trying out this blackjack strategy at an online casino UK.

What is Card Counting in Blackjack?

Put simply, card counting is a system that keeps track of the cards dealt and the cards still in the deck to determine whether the player or dealer has an advantage for the next round. When the odds are in your favour, players typically raise their bets. On the other hand, if you know the odds are in the dealer’s favour, players tend to place smaller stakes.

Before we get into all the details of blackjack card counting and the step-by-step of how it works, it’s important to address some common card counting misconceptions.

To set the record straight, card counting is legal in the UK. You often hear blackjack players asking why is card counting illegal, but the truth is that while it’s not illegal, it is highly frowned upon by casinos, but more on that later.

There are pros and cons to card counting, so if you’re considering whether you should do it or not, there are reasons for both. Starting with the pros, card counting could be a useful strategy to help you make better decisions with your cards if done right.

As you may already know, blackjack is a game of skill and chance, so there are strategies which can improve your chances of winning. If you don’t know what to do with your cards, the house edge would significantly increase in the casino’s favour.

The only reason you should count cards is to increase the odds further in your favour, but there are reasons against it to consider as well. First, if you’re applying this strategy in a land-based casino, you must remember that your behaviour will be monitored closely at all times, and staff know exactly what to look for to spot card counters. They also have several tools and systems in place to detect these players. If spotted, the chances are that you’ll be asked to leave the table or even banned from the casino permanently.

Also, remember that while card counting might be effective in a physical casino, the situation in online or live blackjack is very different. Online casinos use continuous shuffle machines that shuffle the cards every game round, making card counting impossible.

Live blackjack games also use these machines, and you might even notice the dealer placing the used deck of cards into a machine once they’ve dealt the cards. This makes it very difficult to predict what cards can be left in the shoe.

How Does Card Counting Work?

Now that we’ve gone over the pros and cons of counting cards, we’ll answer the question, ‘How does card counting work?’ in further detail by going over the process step by step. To follow any card counting strategy, you must keep a running count of how many high and low cards are dealt.

Here’s how to do it:

  • Assign a value to each card - Cards should be assigned a value of +1, 0, or 1. The cards from 2 to 6 are usually assigned a value of +1, cards 7 to 9 are given a value of 0, and cards 10 to Ace are given a value of -1.
  • Running count - The goal is now to keep a running count of all the cards dealt using the assigned values. Every time a card is dealt, you must keep count using these card values.
  • Make decisions based on your count - If you keep an accurate count of the cards, you should get a positive or negative running count. If the running count is positive, this indicates that the cards left in the deck are big numbers, so you should increase your bet.
  • If the running count is negative, this indicates that the cards left are smaller ones, so you can decrease your bet.

In theory, card counting is quite straightforward, but once you start applying the steps in practice, you’ll realize that it’s not always as easy as it looks. If done successfully, however, the house edge can potentially be reduced to 0.5%, which is a very favourable number that can help you make the most of your casino deposits.

It's worth pointing out that basic strategy can also reduce the house edge, and it’s arguably a lot easier to master than counting cards. You can even use a basic strategy cheat sheet instead of memorising every part of the strategy, and more importantly, using basic strategy isn’t frowned upon by casinos.

How To Use Card Counting Trainer?

Several card counting trainer programs and simulators are available on the internet, designed to help you practice the strategy without any risk and master the card counting basics. A card counting trainer is a software that teaches you how to count cards properly, and it’s a great tool to use if you’re interested in learning the strategy in a risk-free environment. These tools use online blackjack games without real money so you can practice the strategy until you get it right.

If you don’t know how to use a blackjack card counting simulator, you can follow the steps below for any trainers you might find online:

  1. Memorise the card counting values that should be assigned to the cards, as described above.
  2. Press’ Play’ When you’re ready to start, and the cards will be dealt. Your card counting trainer might also give you the option to choose the speed of the practice.
  3. The goal is to learn how to count cards accurately rather than quickly. You can focus on your speed once you perfect your blackjack card counting.
  4. When the cards are dealt, calculate the value of each one on the table and add them together to get the overall value within the time limit. Remember to add and subtract the values to get the overall amount.
  5. Type in your count and click ‘submit’. The trainer will then tell you if your count was correct or not.
  6. If your count is wrong, the card counting simulator will show you the correct count.
  7. If your guess is correct, the round continues, and you will keep submitting your running count to see if you’re accurate or not. Remember, your running count in the second round should be the sum of the first count and the second one. The third count will be the sum of previous rounds, and so on.
  8. When you get a few rounds with 100% accuracy, you’ll be ready to play a real card counting blackjack game with more confidence in your skills.</li.

Hi-Lo Card Counting

Blackjack card counting comes in several forms, and over the years, blackjack enthusiasts developed multiple card counting 21 strategies. The most common way of counting cards is the Hi-Lo strategy, which is also the one that most card counting trainers use.

In the Hi-Lo card counter strategy, cards are assigned the following card values as shown in the table:

Card Value
Cards 2 to 6 +1
Cards 7 to 9 0
Face cards and Ace -1

The Hi-Lo strategy is fairly simple to learn and the one we recommend starting with if you’re a beginner to counting cards. As long as you remember the values which should be assigned to the cards, you should be able to keep a running count fairly easily.

When the dealer deals the first card, take note of the value (-1, 0, or +1). When the next card is dealt, add that card's value to the first card's value, adding or subtracting the number depending on the assigned value. For example, if you set a value of -1 to the first card and +1 to the second, your running count should be zero.

The process should be repeated every time a new card is dealt, adding or subtracting accordingly until the deck is shuffled. If your card count is negative, your bet should be increased on the next round. A positive card count indicates you should lower your bet.

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Advanced Card Counting Strategies

If you’re new to blackjack card counting online, we recommend mastering the Hi-Lo strategy to count cards first. Then, you can progress to more advanced strategies if you’re interested in learning different strategies to try out at a live casino blackjack table or, even better, in a land-based setting.

Below are some advanced card counting UK strategies you can try out:

  • Omega 2 – This card counter system was developed by Bryce Carlson in 1992. It uses zero as a base and is a little more complex than the Hi-Lo system because there are more values. Cards 2, 3, and 7 are assigned a value of 1, cards 4 to 6 get a value of 2, the nine is valued as -1, while the eight and the Ace cards have a value of 0. Lastly, the 10 and the face cards are assigned a value of -2. With this system, a positive running count indicates that there are more low cards left in the deck
  • Wong Halves – Created by Stanford Wong, the Wong Halves system became relatively popular in 1975 when Wong published his book ‘Professional Blackjack’. This system is even more complex because some values aren’t whole numbers. Cards numbered 2 and 7 are assigned a value of +0.5, the 5 is +1.5, cards 3, 4, and 6 have a value of +1, the 8 has a value of 0, the nine is -0.5, and the face cards (and 10) have a value of -1. The Wong Halves system is known as a balanced system, which means that after all the cards in the deck have been dealt, you should have a count of zero.
  • Multiple Decks – Learning how to count multiple decks is a bit trickier than keeping count of a single deck, but it’s the only system that might work if you come across a dealer or blackjack variant using multiple decks. To count multiple decks, you can use the Hi-Lo card counting system by dividing your running count by the number of decks used. The problem with this system is that you need to know exactly how many decks are being used to count cards accurately.
  • Team Play – Finally, one of the most effective ways to put card counting into practice is by doing it in a team. You might already be familiar with this strategy if you’ve seen popular Hollywood films where a group of players use card counting to beat the dealer. The benefit of trying card counting as a team is that it’s easier to keep a count if each team member is responsible for keeping track of specific values, but it’s harder to avoid being detected by casino staff. For this reason, many card counters who go as a team use signals to communicate.

History of Card Counting

Card counting originated around 1962 with Edward Thorp’s book Beat The Dealer. The American mathematician was one of the first to devise a system for counting cards. It was the first mathematically proven system for beating the dealer. Nowadays, the exact method outlined by Thorp in his bestselling book can’t be applied in a casino because of the measures put in place to catch card counters.

Before Ed Thorp, a few other blackjack experts attempted to come up with different card counting systems and methods to beat the dealer. One of these was Jess Marcum, one of the lesser-known blackjack experts and the first to figure out how to count cards. There was also Harold Smith Sr, who counted cards and bet accordingly to beat casinos. He also published a book titled In Want to Quit Winners, just a year before Thorp’s Beat the Dealer.

After Thorp, Marcum, and Smith Sr, Peter Griffin was also considered one of the best card counters in history. He was a mathematician and one of the members of the Blackjack Hall of Fame. In 1981, he published The Theory of Blackjack: The Complete Card Counter’s Guide to the Casino Game of 21, and he was also one of the first blackjack players to calculate the game’s house edge as a percentage.

Is Card Counting Illegal?

Before you try out any system designed to help you improve your odds of winning at a casino game, it’s important to ensure it’s a legal system allowed at casinos. To be clear about the legality of counting cards, there are no laws against card counting in the UK or anywhere in the world.

Some states don't let you count cards by using an electronic device, such as a smartphone card counter app by law, for example, but not in the UK. The state of Nevada is one of the states that have laws against card counting with an app or electronic device, but using your own mathematical skills and counting cards in your head is perfectly legal.

This means that casinos don’t have the authority to persecute or seek any legal action against card counters, but they do have the authority to ask players suspected of using this system to leave. They also employ several measures to make it difficult for players to count cards, such as forcing a shuffle in the middle of a game and switching dealers.

As for playing online blackjack, the situation is a bit different because a real dealer doesn’t shuffle the cards, and multiple decks are used. More importantly, both online table games and live casino games like live blackjack or live baccarat, which involves dealing cards, use a continuous shuffle machine (CMS) to prevent card counting and ensure the game can’t be rigged.

In summary, card counting online blackjack isn’t an ideal strategy because keeping a running count is virtually impossible. With a CMS, you can’t use any card counter system that works with a single deck used by a dealer in a real casino, which is why most card counters only attempt this system when they visit land-based casinos.

Card Counting FAQs

What is Card Counting and Why is it Illegal?

Card counting is a system to keep track of the value of the cards dealt to keep track of how many low or high cards are left in the deck. Essentially, it’s a system of keeping track of the cards dealt to determine who has the advantage in the round between you and the dealer. Many believe that the card counting practice is illegal, but this is, in fact, untrue. Counting cards is legal, but casinos don’t take kindly to using this system and usually ban players who are suspected card counters.

Is Card Counting Legal in the UK?

Yes, card counting is 100% legal in the UK because no laws specifically prohibit it. However, casinos view this blackjack strategy differently and don’t usually allow players to do it. Casino staff are trained to catch card counters and have the authority to ban them.

How Does Card Counting Work?

The blackjack card counting strategy works with a system of assigned values. In the most common method, cards are given a value of -1, 0, or +1 every time they’re dealt. With these values in mind, you can keep a running count of the value of the cards dealt and then use that value to decide whether you should increase or decrease your bet. Some players use a blackjack card counting chart to learn the system, but a card counting trainer is an even better way to practice.

How do Casinos Know if You're Counting?

Casinos can recognise card counters in many ways, sometimes even employing former card counters to spot the signs. They can also tell when someone increases their bet when the count is high and decreases when it is lower. Land-based casinos also take measures to prevent card counting, such as using automatic card shuffling machines to make it virtually impossible for counters to keep track.

Can Casinos Punish You for Counting Cards?

Yes, casinos can ask you to leave the premises if you’re caught counting cards and, in some cases, might even ban you from the casino permanently. As we’ve mentioned in this card counting guide, casinos don’t like it when players use this system and take it very seriously.

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