Blackjack is a card game in which players compete against the dealer. Each player has two cards that are dealt face down and the dealer has one card that is faced up. The goal is to get a higher hand than the dealer. Players can take insurance or surrender if they think the dealer has a blackjack. If the dealer has a blackjack, the player loses the original bet and wins an equal amount on the insurance bet.

The rules of blackjack vary from casino to casino. Some allow the splitting of aces and 8s, while others do not. Some casinos also let you double down after a split. Some even have an early surrender option, where you can forfeit half of your wager before the dealer checks for blackjack. In general, the rules of blackjack are designed to give the house a small advantage over the player. This advantage is based on mathematical calculations and millions of hands played. It is possible to minimize the house edge by following basic strategy, which is a set of rules for playing each hand in a given situation.

A card value chart for blackjack can help you understand the odds of getting a certain hand. A chart shows the probability of each card being a 10, jack, queen or king, and it also tells you when to hit and when to stand. This chart will help you make the right decision in any situation, no matter what your starting cards are.

In blackjack, the dealers must hit on soft 17 – a hand of 17 with an ace counted as a value of 11. The dealer must also hit on a hard 17, which is a hand that has no aces or tens. However, some casinos require the dealer to hit on soft 18 and hard 17.

Players may bet against the dealer by placing chips in front of them. This is called “posting”. The dealer will then look at his or her cards before dealing to each player. A player can also choose to buy insurance, which is a side bet that the dealer has a blackjack. This bet pays 2 to 1 if the dealer has a blackjack. Players should only purchase insurance if they believe that the dealer has a high probability of having a blackjack.

A player’s hand must be closer to 21 than the dealer’s to win. If the player busts, he or she loses, even if the dealer has a blackjack. A two-card blackjack, also known as a “natural”, is an automatic winner and is paid out 3:2 in most casinos. However, some casinos have started to pay only 6:5 on blackjacks, a move that is decried by longtime blackjack players.