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How to Count Cards in Blackjack - It Won't Work Online
Card counting doesn't work in online blackjack. The reason is simple: online blackjack works by constantly shuffling the deck, so the card memory lost after each hand resets the deck to a fresh state.
What's more, even in online live dealer games – the ones with actual cards – a continuous shuffler or early reshuffle usually kills off the chance to count, by negating the card depletion that counting relies on in a physical shoe.
Why counting works in a shoe
Card counting works in a physical blackjack game with a shoe. By tracking the count of high cards vs. low cards, a card counter can increase the average bet during a skewed deck composition and even come out ahead. With a favourable count and good table rules, this can give a skilled player a small edge in a physical game.
But the game is not counted in the same way in online blackjack. Card counting relies on the fact that cards remain in play and leave the game. What was dealt is no longer there to appear again.
The Random Number Generator, or RNG, that underpins an online casino makes blackjack a different animal, and card counting is a complete waste of effort. Online RNG blackjack is not dealt from one consistent physical shoe. Instead, each RNG blackjack game deals from individually reshuffled decks.
The house edge commonly sits around 0.5% for a player using basic strategy under common rules.
Why live dealer usually shuts it down too
Live dealer blackjack games should work better for a count, you’d expect. They feature real cards from a physical deck, which is what a card counter needs. But a close look at how many of these online games work quickly shows the same state that stymies a card count in RNG blackjack. Many live dealer tables use a continuous shuffling machine (CSM), which returns played cards to the machine after each round. This defeats the card depletion that counting depends on, as does an abrupt reshuffle before the shoe's end.
What basic strategy actually does
The technique that reduces the house edge in blackjack is called "basic strategy", and it has nothing to do with counting cards. It tells you to hit, stand, split, or double down on every hand, based on your hand and the dealer's upcard.
Basic strategy is derived from the mathematics of the game. It optimizes the expected value of the player's hand, based on probability. The optimal play is calculated for each hand, and the best way to play it is determined. Card counting is not part of basic strategy.
Under favourable rules, basic strategy can reduce the house edge to around 0.5%. Basic strategy is a set of rules that tells an optimal blackjack player how to play the game, but it does not involve card counting.
The practical answer for online players
The conclusion is that card counting is a dead end in both RNG blackjack, where each hand is dealt from a freshly shuffled deck with no game memory, and in most online live dealer games, where a CSM or early reshuffle neutralises card depletion. Basic strategy offers the best shot at reducing the house edge, but it doesn't eliminate it.
So in summary, while card counting can be an effective strategy in physical blackjack games, it is not a viable option in online blackjack, where the game is reshuffled before the cards in the shoe reach a critical level of depletion. In Ireland and anywhere else, basic strategy is a better and straightforward way to play blackjack.