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The High-Low Card Counting System Explained

The High-Low system (or Hi-Lo) is the most widely used card counting strategy in the world. Introduced by Harvey Dubner in 1963, it strikes the perfect balance between power and simplicity.

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Why It Works

Blackjack is beatable because the odds change as cards are removed from the deck. The High-Low system tracks this change by assigning a value to every card.

  • Small cards (2-6) are bad for the dealer but good for the player. When they are removed, the deck becomes richer in high cards.
  • Big cards (10-Ace) are good for the player. They increase the chance of Blackjacks (which pay 3:2) and cause the dealer to bust.

The Values

Every card has a tag:

2, 3, 4, 5, 6 = +1
7, 8, 9 = 0
10, J, Q, K, A = -1

How to Practice

Don't start betting money until you can count down a single deck in under 30 seconds with zero errors. Start slow. Use our free trainer to build speed.