Card Counting
A strategy for tracking the ratio of high to low cards remaining in the deck to gain an edge.
Card counting is an advantage play technique in blackjack where you track whether the remaining deck is rich in high cards (10s, face cards, Aces) or low cards. When the remaining deck has proportionally more high cards, the player has an edge.
The most common system is Hi-Lo: cards 2-6 are +1, cards 7-9 are 0, and cards 10-A are -1. You keep a running count, convert to true count (dividing by decks remaining), and increase your bets when the count is positive.
Card counting is legal but casinos can ban you for it. It's not easy — it requires intense concentration, discipline to avoid detection, and enough bankroll to weather significant variance. The edge from counting is typically 0.5-1.5%.
Related Terms
Basic Strategy (Blackjack)
The mathematically optimal play for every possible hand in blackjack.
House Edge
The mathematical advantage the casino has over players, expressed as a percentage of each bet.
Edge
Any advantage a bettor has over the bookmaker or casino on a specific wager.
Bankroll Management
The practice of managing your gambling funds to minimize the risk of going broke.
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