BlackJack – How to Count Cards

The art of counting cards involves a fair amount of focus, but is simpler than most people believe. A player must monitor the cards as they are dealt and keep track of a running total,  they should adjust their wager suitably.


The Basic Technique

It is not essential, as some believe, to keep track of every single card that has been dealt. While it would be useful to know the precise number of each card which remains, it is not required and beyond the capacity of the typical (or even somewhat intelligent) player to do so. Card counting relies on an approximation of the value of the cards that have been dealt, as a suggestion of the ones that remain to be dealt.

This guide is based on the High-Low counting system, in which two, three, four, five, and six cards are valued at +1; seven, eight, and nine are 0 and all ten-value cards and aces are valued at -1. There are numerous other counting systems are available, but the High-Low system is one of the simplest to follow, and suitably effective in practice.

In this system, low cards “add” to the count while high cards “subtract” from it. This is due to the fact that the removal of low cards from the deck increases the amount of high cards left to be dealt, and vice versa. A larger proportion of high cards in the deck favour the player.


Keeping the Count

To keep the count, a player needs to make a mental note of the cards, as they come out of the show, and keep a running total in mind. One technique of doing this is to note the value of every card as it is upturned and keeping a constant tally of the total:


K 6 9 4 6 5 4 7 Q


-1 +1 0 +1 +1 +1 +1 0 -1


-1 0 0 +1 +2 +3 +4 +4 +3

While this is valuable as a training method, the physical behaviours one displays while doing this, constant eye and head movement during the deal, is a very clear signal to casino personnel that the player is a card counter.

A safer technique is to monitor the value of each hand as it is played, it is common for players to watch as others play their hands, logging the total value as a player’s cards are collected:

Player 1 –          K 9


Player 2 –          6 5 7


Player 3 –          2 J 4 8


Player 4 –          A 3 4


Dealer –          Q 8




Using this technique will allow the player to focus on other things while the cards are being dealt. A hand of two high cards has a net effect of -2, two low cards with a high card, +1, a high and a low hit with a high -1, a blackjack is -2, etc.

It needs slightly more practice to learn to count cards a hand at a time as a pose to one-by-one, but it will eventually become second nature, so the work involved in learning this system will result in less effort to use it in an actual playing situation.

Counting in Multiple-Deck Games

Because the count is an approximation of the amount of high cards left in the deck, it must be altered depending on the number of decks that are in use. The running count keeps track of the circumstances, the number of high cards compared to low ones, remaining in the deck. In other words, if four kings are dealt from a single deck, none remain, but if four are dealt in a game using four decks, twelve remain.

The simplest way to approximate the “true” count from the running count is to divide the running count by the number of decks used in the game. A running count of +8 is worth +8 in a single-deck game (8/1), but +4 in a two-deck game (8/2), +2 in a four-deck game (8/4), and +1 in an eight-deck game (8/8).

A more precise method to approximate the “true” count involves dividing the running count by the number of decks that wait to be played. If the running count is +15 in an eight-deck game, but two decks have already been played, the true count would be +2.5 (+15 divided by 6 remaining decks), and +5 (+15 divided by 3 remaining decks), when five decks have been played.


Wagering based on the count

To put it simply, you should up your wager when the count is in your favour and decrease it (or leave the game) when it is not.

The simplest system for doing this is to increase your wager one unit for every value of the true count. Once the deck has been shuffled, bet one unit. If the count rises to +2, wager three units (one plus two). If it drops to -1, bet zero, sit out for a round. If it drops lower than -1, continue sitting out or leave the table.

While this is mostly sound advice, a player who frequently sits out hands may be asked to leave the table in order to allow others to play. Additionally, a player who changes tables frequently, winning small sums at each, will swiftly be identified as a counter and asked to leave the casino altogether.

In order to maximize your playing time, and lower the risk of being detected as a counter, it may be required to stay in the game at a one-unit wager, even when the deck is in favour of the dealer. While this costs some profits, it will enable you to stay in the game, and the count will be changed with the next shuffle.

Common sense is required. If you’re approaching the end of a session, or if the count drops to an appalling level with plenty of rounds waiting to be dealt before the next shuffle, there may not be sufficient time or opportunity to recoup the losses you’ll sustain by waiting for the count to turn. Walk away, and come back later.


Insurance and Even Money

In most situations, insurance and even money are sucker bets; a 3:1 payoff on a 30.7% chance gives a 2.6% edge to the house. But, since the odds of an unknown card being a ten-value card increases around 0.5% times the count, these bets become almost fair when the true count stands at +5, and shifts in favour of the player when the count surpasses that level.

Since the majority of players decline these side bets, taking them (particularly after constantly refusing them in the past) may draw suspicion. To stay in the game, and on the site, it may be sensible to pass on these opportunities, or to take advantage of them only once in a while.


Alterations to Basic Strategy

Basic strategy is based on the likely results from a freshly-shuffled deck; it should be altered based on the count. Try to keep the following adjustments in mind:

When the count is +5 or above

  • Take insurance and even money
  • Stand on 12 against a deuce or a three
  • Stand on 15 or 16 against a ten
  • Double 8 or 9 against a five or six
  • Double any soft 13 to 16 against a six or lower

When the count is +10 or above

  • Stand a 14, 15, or 16 against anything
  • Double any soft hand less than 19 against a six or lower
  • Double 8 or 9 against a four
  • Double 10 against a ten
  • Double 11 against an ace
  • Split fours against three, four, five, or six
  • Split fives against a four, five, or six
  • Split tens against a five or six

When the count is +15 or higher

  • Double a soft 19 against a six or lower
  • Double any hard hand less than twelve against six or lower
  • Split tens against anything less than a nine
  • Split fours, fives, and sixes against anything less than a seven