Card Counting in Blackjack: How It Works

Card counting is a strategy used in blackjack to determine whether the next hand is likely to give an advantage to the player or the dealer. It involves tracking the ratio of high cards to low cards remaining in the shoe. When the count favors the player, you increase your bets.

The Hi-Lo system assigns values to cards: +1 for 2-6, 0 for 7-9, and -1 for 10-A. As cards are dealt, you keep a running count. A high positive count means more high cards remain, which is favorable for the player. Convert to a true count by dividing by remaining decks.

Card counting is ineffective at online casinos because the virtual deck is shuffled after every single hand, resetting any count advantage. Even live dealer games typically use automatic shufflers or shuffle after 50% shoe penetration, severely limiting the effectiveness of counting.

Card counting is not illegal but casinos can and do ban suspected counters. In practice, successful card counting requires significant practice, discipline, and a large bankroll to withstand variance. The mathematical edge, even when counting, is only about 1-2%.