It's pretty much accepted that it's possible to count cards at land-based casinos. But many players will point out that counting cards are impossible at online casinos. In truth, this isn't true. It's perfectly feasible to count cards with online live dealer games. Having said that, much will depend on how often the dealer shuffles the decks. Or, as it's better known, the deck penetration. This is the most important factor and will decide if you'll end up making a decent profit over time.
We've all seen the movies where the fortunes of the characters are suddenly turned around with the discovery that one of them has the ability to count cards. In a matter of hours they win a huge amount and break the bank. Unfortunately, this is just the fiction of Hollywood. And though it's true that back in the day, real gamblers could make a decent living counting cards, those days are now long gone. Today you have to contend with sophisticated casino security. And nothing gets past them.
The blackjack shoe is an invention bought into land-based casinos back in the 1960s. Today, you'll find that every casino, whether online or land-based, will feature some sort of shoe. This can be either automatic or manual. By making use of these card shuffling machines, it makes the job of counting cards in blackjack totally redundant. With up to 8 decks being constantly added to the shoe, and with many being replaced before a complete deck is dealt out, the card counter has no hope.