What Is Card Counting In Blackjack?

Card counting required the player to keep a running mental tally of all cards seen by the player and provide a value to those cards, making play decisions based on the remaining composition of cards. A good card counter will bet more when they determine the advantage to be in their favour while they will attempt to minimise any losses when the advantage is determined to be in the hands of the dealer.

Card Counting Basics

In card counting, aces and 10s, are deemed high cards that benefit the player while low cards, including 5s, 3s, 4s, and 6s, are low cards that benefit the dealer. The higher concentration of high cards the better.

While card counting a player will give each card a positive, negative or zero value. Low cards will have a positive value as that means that the number of high cards remaining in the hand increases, while high cards have the opposite effect.

The count is adjusted based on those values. The Kelly criterion, a mathematical principle, dictates that as the player advantage increases with a higher count, the more the player should increase their bets in order to take advantage of this edge.

Is Card Counting Illegal?

While mental card counting is not illegal, it is frowned upon by many casinos who do their best to prevent the practice. Casinos in most of the United States, the Chinese gambling capital of Macau, and Britain do have the right to remove or ban any player they suspect of card counting. Players found to be using external card counting devices or getting assistance from another player can be liable to fines or arrest as this is deemed illegal.

In New Jersey, Atlantic City casinos are not allowed to ban card counters after the New Jersey Supreme Court ruled in favour of Blackjack Hall of Fame inductee Ken Uston who went legal against an Atlantic City casino. In the lawsuit, the court ruled that casinos could not ban players for their skill.

Card Counting Countermeasures

In order to prevent or limit players from card counting in Blackjack, casinos have implemented a number of different countermeasures. This primarily includes rules around shuffling, including not allowing player entry until after a shuffle, frequent or complex shuffling, shuffling upon player wager increases, or fixing player bets so they cannot change their amount bet during a shoe.

However, this increase in shuffling can slow down gameplay at casinos and any reduction in playing time will affect the house winnings. Thus, many casinos have introduced continuous shuffle machines while allow no interruption to play as any used cards are simply returned and reshuffled into the show. This greatly reduces player card counting abilities.