Edward Thorpe and the Ten Count System

The origins of card counting have been the subject of debate for several decades, with the first Ace counters spotted across Las Vegas casinos in the 1940s and 1950s. The first system for counting cards, that was mathematically proved to be effective, however, was the so-called Ten-Count System, which was presented by researcher and mathematician Edward Thorpe in his 1962 book Beat the Dealer.

Edward Thorpe, known today as the Father of card counting, was a professor of mathematics and finance, as well as a blackjack player and researcher. Using the computational power of some of the first computers, he developed successful models for card counting. Later, he applied his methods in casinos and managed to gain financially from them, although he claimed that his goals were purely scientific. Before him, there were only a few counters who managed to obtain advantage over the casino without cheating. Yet, there were no sophisticated systems for counting and his method for the tracking the cards on the table truly revolutionized the game of blackjack.

Following years of mixed success for advantage players in casinos, Thorpe’s book finally proved the somewhat mythical idea that it is possible to beat the house in its own game. With the help of a blackjack strategy and a specially designed system for counting the 10s in the deck, players were given the opportunity to shift the odds in their favor.

Ten Count System Fundamentals

Basics of the Ten Count System
How to Use Edward Thorpe’s Ten Count System

Basics of the Ten Count System

When it was first demonstrated by Edward Thorpe in the 1960s, the Ten Count System was very impressive – for the first time, a method for “cheating” casinos was supported by clear mathematical evidence. It should be noted, however, that by today’s standards, it is incredibly simplistic, easy to counteract by casinos, and more importantly, it is practically irrelevant because it was designed for single-deck games.

Nowadays, casinos rarely offer blackjack games, which uses only one deck of cards, and when they do, they take certain countermeasures to prevent players from using Edward Thorpe’s counting method. So, what is his system and how does it differ from more advanced methods?

The basic idea of the Ten Count is the same as with all other systems – it assigns different values to the cards and requires the player to keep a count during play. It allows good counters to modify their strategy and change the bet size based on the running count. Thorpe’s system focuses only on the 10-value cards, hence its name – all 10s, Jacks, Queens, and Kings are assigned a value of -9. All other cards (Ace-9) are counted as +4.

The theory behind this method is that 10-value cards are good for the player since the strongest hands – blackjack (natural 21) and a total of 20, are formed with one or two 10-value cards. In a single-deck game, there are 16 ten-value cards in the beginning of the game and the system practically tracks of odds of receiving such a card at any point of play.

How to Use Edward Thorpe’s Ten Count System

Since 10-value cards are counted as -9, whereas all the rest are counted as +4, we simply subtract 9 whenever a 10, Jack, Queen, or King are dealt, and we add 4 to the count in all other instances. It sounds simple but players should learn to do this basic math very quickly while playing. For example, the following cards are being dealt in the first round – the first player receives A-3, the second one gets 8-6, while the dealer’s upcard is a Queen. The count will be 4+4+4+4-9 or 7.

The Ten Count Method do not specify when to increase or reduce the bet size and by how much. Instead, it only suggests that the stakes should be raised at the end of the deck if the count is positive. If its drops below zero, on the other hand, players should reduce the size of their bets. Every decision made during the game should be determined by the basic strategy.

Another form of the same method requires players to keep two counts, rather than one. This would be more difficult, however, especially for new players. The idea, on the other hand, is very simple – the game starts with 16 high cards (10-King) and 36 low cards (Ace-9), so we keep one count for the high and one count for the low cards. Whenever a 10-value card appears on the table, we subtract 1 from 16, and when a low card is dealt, we subtract 1 from 36.

This could be quite confusing at first but its concept is very simple – if the player gets A-6 in the first round against dealer 8, for example, the high count remains 16, while the low count drops to 33. If the low count drops to zero or near zero, the player should increase the bet to the table maximum. If the high count falls dramatically, the player should reduce the bet size to the minimum.

Advantages and Disadvantages of the Ten Count System


The most obvious advantage of this card counting system is its simplicity – even if players keep two counts simultaneously. The method can be learned almost immediately and it could be applied without mistakes by most blackjack players. In comparison, the majority of systems developed after that could be extremely complex and hard to apply in real-life games.

While the Ten Count System was proved to be working in the 1960s, today, it is practically obsolete. Edward Thorpe invented it for single-deck games only, which were quite popular in casinos back then. However, modern blackjack variations are usually played with 4 to 8 decks of cards and the Ten Count method simply does not work.

The other great aspect of the Ten Count System is that it is effective in demonstrating when the deck is rich in high or low cards. This helps players adjust their bet size so they win more whenever the odds of the game are in their favor.

Even in single-deck games, we are now offered less favorable rules than what was a standard once – only a few rounds are played before a reshuffle and the deck is never dealt to the last card. This means that a counter using this method will almost never see the odds shift in his favor. Even if one or two cards remain in the deck, the outcome would be very different than the original calculations made by Thorpe.

The Ten Count System is certainly a method that should be mentioned and learned by all card counters but not because it is effective – simply because it helps players understand the fundamental idea of card counting and the importance of the 10-value cards in the deck. Clearly, it is irrelevant in multi-deck games with restrictions on Doubling, Resplitting of Aces, and other moder changes to the standard rules of the game. Overall, it is a good system to try but it should not be attempted in real-money play in casinos.

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