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KO Card Counting Strategy

There are many card counting systems that are used when playing blackjack and each system has a different level of difficulty and accuracy. One of the easiest systems to use is the KO, or Knock Out system. This system was first used in 1992 and was called the All Sevens system. This is one of the most basic systems used by blackjack players today and it is a perfect system for new card counters. The Knock Out system is an unbalanced counting system that uses a running count. Since this system is unbalanced, there is no need for the calculation of a true count.

Using the KO / Knock Out System

This system does not use all cards in the deck, which is why it is one of the easiest to use. Most of the cards that are counted will be worth +1, which will create the unbalance. The initial running count will start with zero and players will then add or subtract a value based on what cards are in play. The following table depicts the counts for each card that is considered with this system.

Card Value Points
2, 3, 4, 5, 6, 7 +1
8, 9 0
10, Jack, Queen, King, Ace -1

When the running count using this system reaches +2 or higher, it indicates an advantage for the player. The higher the count, the more of an advantage the player will have during the game.

When to Adjust Bets

Using this system, the easiest betting strategy is to increase bet amounts when the player has the advantage and lower bets when the house has the advantage. This betting strategy is based on playing a single deck game of blackjack, but can be altered slightly to accommodate games with multiple decks.

It is important for players to know when to increase and decrease their bet amounts when using this system. The following table lets players know when they should alter their bet amounts based on the running count when playing a single deck game.

When running count is more than 0 When true count is less than 1
The betting amount is the same as the table minimum The bet amount can be calculated as (running count +1) times the betting unit


When playing a game that uses 6 decks, things should be adjusted:

Running count of more than -3 True count of more than, or equal to -3
Betting amount is equal to table minimum Bet amount is 2 times table minimum for -3 and -2 counts and 5 times table minimum for -1 to +1. Increase the bet after each running count increment of 2 by doubling the bet.

House Edge with the KO System

When using this system properly, it is possible to enjoy a house edge of 1% to 2%. The amount that is won from the game will depend on the ability to count cards and alter the bet amounts at the right time. Since the KO system is simple to use and only counts a few of the cards in play, it is a preferred selection for beginner card counters who want an accurate, yet simple system.

More Card Counting Systems for Beginners:

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