The Knock Out or KO count is an unbalanced card counting method popularized in the book Knock-Out Blackjack by Ken Fuchs and Olaf Vancurra. The cards 2-7 are considered +1 while face cards and 10 point cards are considered -1.
Unlike the Hi-Lo Count, the KO count should result in a value of +4 if a full deck is counted down correctly. The big upshot of this system is that players don’t have to go through the extra step of converting to the true count, since in KO count the running count is considered to be “true”.
2, 3, 4 , 5, 6, 7
10, J, Q, K, A
The Knock Out card counting system was designed for people who have trouble keeping track of both running and true count, and making the conversion between the two while playing in a noisy casino. The result is that the KO count is slightly less accurate than the Hi-Lo Count and for this reason it is usually employed by recreational blackjack players.