Why Card Counting Is of No Use When Playing Blackjack Online

Written by Dean McHugh
Dean McHugh
Dean McHugh is a full-time writer with more than 20 years of experience in the iGaming industry. Specialising in casino reviews, slot analyses, and sportsbook evaluations, he delivers clear, engaging, and insightful content for both industry professionals and casual players. Over the past four years, he has contributed extensively to leading iGaming comparison websites.
, | Updated: Wed 27 August 2025

card countingEven if you are not very familiar with the game of blackjack, you have most probably heard of card counting. This method of playing the card game is extremely popular and can even be seen in numerous films set in casinos. Those who are well-acquainted with blackjack know that card counting is a technique that can give them a considerable edge over the house and can consistently lead to favourable results.

While players regard card counting as a strategy developed for successful yet fair gameplay, you will rarely come across a casino that tolerates this technique. In fact, card counting can often be the reason for being kicked out of large casinos – that is, of course, if you are caught.

Although card counting is a risky endeavour, many players attempt to develop this skill in order to overcome the house’s advantage at brick-and-mortar casinos. Those who are willing to employ this method and manage not to get caught can enjoy a rather successful blackjack experience. However, this is only true if they play at land-based casinos. Players who prefer to play blackjack online will not have the same luck, as this system is virtually useless at online casinos.

To prevent players from gaining an advantage over the house, online casinos take various steps that do not allow players to count cards while playing blackjack. That is why players who are used to making a profit through card counting might want to reconsider their strategy and look for another way to improve their virtual blackjack sessions.

How Card Counting Affects Blackjack Play

Card CountingWhen discussing card counting, we should mention the term deck penetration, as it affects the accuracy of the counting strategy. It refers to how many cards have been dealt before the deck is reshuffled. Deck penetration is typically expressed as a percentage, and the higher this percentage is, the more accurate the card count will be. The fewer decks that are used in the game, the higher the penetration rate will be, giving players a more accurate card count.

While it is more difficult to count how many cards remain before reshuffling, it is possible to achieve adequate deck penetration in blackjack variations with four, six, or even eight decks. There are, however, several conditions that must be met to ensure that a multi-deck blackjack game will be in the player’s favour.

To achieve good deck penetration, variations that use many decks must not reshuffle the shoe after every hand that is played. For instance, there are six-deck blackjack options that reshuffle the shoe only after five of the decks have been dealt. In such a case, players have the chance to turn the tables by card counting and achieve a respectable level of deck penetration.

Although the concept of deck penetration applies to blackjack played in land-based casinos, when the game is played online, card counting offers players little assistance. You might think that live-dealer blackjack games would allow you to count cards, as they are almost identical to the blackjack offered at brick-and-mortar venues. However, this is not entirely true, as even live-dealer blackjack games contain rules and safeguards that prevent players from counting cards successfully.

Is Card Counting Possible While Playing Online Blackjack?

Card Counting onlineWhen playing blackjack online, you should be aware that the experience will be different from the one you are used to when visiting land-based casinos. Whether you are playing RNG blackjack or have chosen to play online with a real dealer, you will not benefit from counting cards, as the design of virtual blackjack games prevents deck penetration almost entirely.

While live-dealer blackjack is very similar to the game offered in land-based casinos, several techniques are still employed to prevent deck penetration from exceeding 50%. Of course, many players still attempt to find such live tables, but they rarely succeed in finding a live blackjack table with a deck penetration of over 50%.

Even though both live-dealer and RNG blackjack games are designed to prevent deck penetration, the techniques employed in the two types of virtual casino games differ. To better understand why card counting does not work in online blackjack variations, it is useful to explore the two formats separately.

RNG online blackjack games and card counting

RNGRNG virtual blackjack games do not have a shoe to penetrate, nor is there a dealer who reshuffles the cards at any point. Instead, the cards that are dealt are chosen randomly by a piece of software known as an RNG (Random Number Generator). The same software ensures that the cards are always shuffled, making card counting a futile strategy when playing online blackjack games.

Live blackjack games and card counting

Live blackjack gamesLive blackjack online is played differently, as the game uses a real dealer who deals and shuffles cards in real time, just as in every land-based casino. However, this type of virtual blackjack also does not allow adequate deck penetration, rendering card counting useless once again. The shoes used in live-dealer blackjack games are typically shuffled with the help of Continuous Shuffling Machines. If that is not the case, dealers will shuffle the cards once the middle of the shoe is reached, making card counting ineffective.

Other Techniques Used by Online Blackjack Games to Prevent Card Counting

Other TechniquesWhile land-based casinos can often ban players from entering their gaming facilities if they are caught counting cards, online casinos cannot actually stop you from using this strategy. Instead, virtual blackjack games employ measures to make card counting ineffective. As counting cards provides no real advantage, online blackjack players often resort to other strategies to gain an edge during play.

Fewer rounds played per hour

Fewer rounds played per hourCompared to land-based blackjack, online blackjack sessions are far slower. Players who utilise card counting are accustomed to playing through an average of 100 to 200 rounds per hour when playing offline. However, online blackjack is much slower, as every choice must be made by tapping various buttons. Combined with the time each player at a live table is given to make a decision, online blackjack sessions may manage about 50 rounds per hour at best.

Slower gameplay definitely has a negative impact on card counting, as it is difficult to achieve meaningful deck penetration at such a slow pace.

Monitoring of gameplay through specialised software

Monitoring of gameplayTo further deter players from using a card-counting strategy when playing blackjack online, virtual casinos utilise monitoring software. This software tracks how much of the shoe has been used in the game before a reshuffle occurs. Many interactive casinos have also invested in AI that can detect card counting through the betting patterns of players employing the strategy. If a player’s wagers consistently correlate with the card count, the casino is alerted and the player is prevented from placing further bets on the game.

Can You Still Make Profit from Counting Cards in Online Blackjack?

ProfitWhile it is not impossible to count cards while playing blackjack online, we believe this will be a largely fruitless endeavour. To make your gaming sessions even somewhat successful when counting cards, three different factors must be present during the gameplay:

  • Favourable rules
  • High deck penetration
  • Sufficient number of rounds played per hour

As we have already discussed, all three of the above factors are seldom present in online blackjack variations. This is why there is rarely any advantage to card counting when you play online. Better deck penetration is possible in land-based games of blackjack, as casinos cannot afford to reshuffle after every hand. Because constant reshuffles would slow down the gameplay, this would result in fewer rounds being played – the last thing a land-based casino would want.

However, lost time is not a concern for virtual casinos, as they utilise software to reshuffle cards automatically, allowing very little deck penetration. In such a scenario, you do not stand a chance of gaining any advantage by counting cards.

If you are playing a live-dealer blackjack variation, you might enjoy slightly better deck penetration, as such games are dealt by real dealers. However, virtual casinos are well aware of players attempting to gain a significant advantage by counting cards when playing live blackjack. For this reason, the dealers who handle the cards on live tables are trained to reshuffle the shoe before more than half of the decks have been used. Finding a live-dealer blackjack table with a deck penetration of over 50% is therefore very difficult, rendering card counting useless once again.

Another factor to consider when playing online blackjack is that you will need a larger spread to gain an advantage with low deck penetration. For example, suppose you are playing a blackjack game with a minimum bet of £5 and you decide to raise your wager to £75 when the true count is +3. If we divide your increased bet by the minimum wager of £5, we obtain a bet spread of 1-15.

Professional card counters usually prefer to play with a bet spread ranging between 1-10 and 1-15. However, such a spread is often indicative of card counting, so players must be careful when placing their bets. While land-based casinos can be very strict in monitoring players for card counting, online casinos are typically more forgiving when players adopt suspiciously large bet spreads. This, of course, stems from the fact that they do not allow sufficient penetration for card counters to benefit from using big bet spreads.

If you are playing an online blackjack game with only 50% penetration, you will need to increase your maximum bet further and play with a bet spread of about 1-30. Using the example above, a table with a minimum bet of £5 would require you to raise your stake to £150 when the true count reaches +3.

There is a possibility of trying to gain greater advantage by wonging in, which is the tactic of simply monitoring the game and only sitting at the live table at points that may be favourable for you. This strategy allows you to lose less money by avoiding bets before the count becomes positive.

It should be noted, however, that even if you wong in at a positive count and use a 1-30 bet spread, you will not enjoy a very profitable blackjack game in a live-dealer variation with a deck penetration of 50%. This level is far too low to gain any real advantage by counting cards. Moreover, you will end up investing a great deal of time for a very insignificant profit.

Keep Card Counting for Offline Blackjack Games

Card Counting offlineIf you have invested a lot of time in learning card counting, it is simply not worth using the skill at online casinos. Virtual blackjack games contain rules and conditions that are not beneficial for players who keep track of the cards that have already been dealt. While it is possible to count cards while playing live-dealer blackjack, the experience is unlikely to be fruitful.

Although many blackjack aficionados can confirm that card counting is a highly profitable skill that can help you gain an advantage over the house, almost none of them would consider using it at online casinos. With live-dealer blackjack tables offering an average deck penetration of 50%, you are unlikely to amass any significant winnings.

We recommend employing a different strategy when playing blackjack online, as card counting offers little assistance in this environment. With rules that are far from ideal, very low deck penetration, and fewer rounds per hour, card counting cannot bring you any significant profit when playing virtual blackjack games.

Related Articles