Card Games
How to Play Blackjack
A card game against the dealer with a target of 21; the one table game where player decisions change the house edge.
Blackjack sets each player against the dealer rather than against the other players at the table. The best hand is the one closest to 21 without going over. A hand worth more than 21 is a bust and loses at once, whatever the dealer later holds.
Blackjack occupies a special place among casino games because player decisions affect long-run results. A player following basic strategy faces a house edge of around half a percent, while a player deciding on instinct faces roughly two percent, or four times as much. This guide sets out the table rules, every decision available, the basic strategy tables, and the effect of each rule variation.
Card Values and Hand Totals
Number cards are worth their face value, picture cards are worth ten, and an ace is worth one or eleven as the hand requires. A hand counting an ace as eleven is called a soft hand; a hand with no flexible ace is a hard hand.
| Card | Value |
|---|---|
| 2 through 10 | Face value |
| Jack, Queen, King | 10 |
| Ace | 1 or 11, whichever suits the hand |
An ace with a ten-value card on the first two cards is a blackjack or natural. It pays 3:2 at a standard table and beats any 21 built from three or more cards.
The Rules That Bind the Dealer
The dealer makes no decisions. They follow fixed rules printed on the table, and those rules determine most of the odds of the game.
- Stands on 17. The dealer draws until reaching a total of 17 or more, then stops. This is printed as dealer stands on all 17s.
- Hits soft 17. At some tables the dealer must draw on a total of 17 that counts an ace as eleven. This rule adds about 0.22% to the house edge.
- The hole card. The dealer holds one card face up and one face down. The face-down card is revealed only after every player has finished.
- Ties. When a player total equals the dealer total the stake is returned in full. This is called a push.
The Six Decisions Available
Decisions are conveyed by hand signal rather than by speech, so that they are recorded by the camera above the table. The standard signals are explained on the casino table etiquette page.
| Decision | Meaning | Signal |
|---|---|---|
| Hit | Take one more card | Tap the table with a finger |
| Stand | Take no more cards | Wave a flat hand over the cards |
| Double down | Double the stake and take exactly one card | Add chips beside the original bet |
| Split | Separate two cards of equal rank into two hands | Add chips and make a V with two fingers |
| Surrender | Give up the hand and lose half the stake | Draw a horizontal line behind the bet |
| Insurance | A side bet offered when the dealer shows an ace | Place chips on the insurance line |
Insurance pays 2:1 and wins when the dealer's hole card is worth ten. The chance of that is about 30.8% in a six-deck game, while the payout would require better than one in three to break even. The house edge on the bet is around 7.5%, which is why basic strategy never takes it.
How a Round of Blackjack Is Played
A single round of Blackjack follows the sequence below. The same sequence applies at a physical table and at a live dealer table streamed to a screen.
- Place a bet in the betting circlePut chips in the betting circle in front of the seat before the dealer begins to deal.
- Receive the first two cardsEach player receives two cards, usually face up. The dealer takes one card face up and one face down.
- Check for blackjackIf the first two cards total 21 the hand pays 3:2 and is finished, unless the dealer also has blackjack, in which case the stake is returned.
- Compare the hand with the dealer upcardFind the row for the hand in the basic strategy tables, then read off the decision for the dealer's upcard.
- Signal the decision by handTap the table to hit, wave a flat hand to stand, add chips to double or split.
- Play the hand outA hand may take further cards until the player stands or the total passes 21.
- The dealer completes their handThe hole card is turned over and the dealer draws until reaching 17 or more as the table rules require.
- Bets are settledThe higher hand wins and pays 1:1. Equal totals return the stake.
Basic Strategy Tables
Basic strategy is the list of decisions with the highest expected value for every combination of player hand and dealer upcard. The tables below apply to a six-deck game where the dealer stands on all 17s and doubling after splitting is allowed.
Hard hands
| Player hand | Decision |
|---|---|
| 8 or lower | Hit |
| 9 | Double against a dealer 3 to 6, otherwise hit |
| 10 | Double against a dealer 2 to 9, otherwise hit |
| 11 | Double against a dealer 2 to 10, otherwise hit |
| 12 | Stand against a dealer 4 to 6, otherwise hit |
| 13 to 16 | Stand against a dealer 2 to 6, otherwise hit |
| 17 to 21 | Stand |
Soft hands
| Player hand | Decision |
|---|---|
| Ace and 2, or ace and 3 | Double against a dealer 5 or 6, otherwise hit |
| Ace and 4, or ace and 5 | Double against a dealer 4 to 6, otherwise hit |
| Ace and 6 | Double against a dealer 3 to 6, otherwise hit |
| Ace and 7 | Double against 3 to 6, stand against 2, 7 or 8, hit against 9 to ace |
| Ace and 8, or ace and 9 | Stand |
Pairs
| Pair | Decision |
|---|---|
| Ace and ace | Always split |
| 8 and 8 | Always split |
| 10 and 10 | Never split, stand |
| 5 and 5 | Never split, treat as a hard 10 |
| 9 and 9 | Split against 2 to 6 and 8 to 9, otherwise stand |
| 7 and 7 | Split against 2 to 7, otherwise hit |
| 6 and 6 | Split against 2 to 6, otherwise hit |
| 4 and 4 | Split against 5 or 6, otherwise hit |
| 3 and 3, or 2 and 2 | Split against 2 to 7, otherwise hit |
None of these decisions is affected by the result of the previous hand or by the number of players at the table. A player following the tables in full faces a house edge of about 0.46%.
How Rule Variations Change the House Edge
Two blackjack tables that look alike can carry house edges several times apart. The table below shows the change from a baseline of 0.46% under standard six-deck rules.
| Rule | Change in house edge |
|---|---|
| Blackjack pays 6:5 | Up 1.39% |
| Dealer hits soft 17 | Up 0.22% |
| Doubling restricted to totals of 10 and 11 | Up 0.18% |
| Doubling after splitting not allowed | Up 0.14% |
| Eight decks instead of six | Up 0.02% |
| Re-splitting aces allowed | Down 0.08% |
| Late surrender allowed | Down 0.07% |
| Single deck with all other rules unchanged | Down 0.48% |
The order of checks before choosing a table is: the blackjack payout, the soft 17 rule, then the doubling rules. A 6:5 payout pushes the edge of the table above that of single-zero roulette even for a player using basic strategy.
Card Counting and Where It Stands
Blackjack is a game in which the remaining composition of the shoe affects the odds, because cards already dealt are not returned until the next shuffle. Card counting exploits that by tracking how many high cards remain.
The practice is not illegal, but casinos are entitled to refuse service to players who use it, and they generally respond with continuous shuffling machines, shallow deck penetration and camera surveillance that remove the advantage. At online tables shuffled after every round, counting has no effect whatsoever.
Blackjack Terminology
The terms below are the ones heard most often at the Blackjack table. A wider list is available in the casino glossary.
- Bust
- A hand worth more than 21. It loses immediately, even if the dealer later busts as well.
- Push
- A tie between player and dealer, which returns the stake in full.
- Soft 17
- A total of 17 that counts an ace as eleven, such as ace and 6.
- Double down
- Doubling the stake on condition that exactly one more card is taken.
- Surrender
- Giving up a hand after seeing the dealer upcard, at a cost of half the stake.
- Basic strategy
- The list of decisions with the highest expected value for every combination of player hand and dealer upcard.
- Penetration
- The share of the shoe dealt before a reshuffle, which sets how deeply the decks are played.
Blackjack FAQ
Does blackjack have the lowest house edge in the casino?
Under standard rules and with basic strategy it is about 0.46%, among the lowest of any table game. A few bets in craps and some full-pay video poker machines go lower still.
Why should insurance be declined?
Insurance pays 2:1, while the chance that the dealer's hole card is worth ten is only about 30.8% in a six-deck game. That gap leaves a house edge of roughly 7.5%, far above the main bet.
Do the decisions of other players affect my hand?
Not over the long run. Another player's decision does change which card you receive on a given hand, but the effect runs in both directions and cancels out, leaving expected value unchanged.
What does a 6:5 blackjack table mean?
A blackjack on a 100-unit bet pays 120 units instead of 150. The change adds about 1.39% to the house edge and is the single most costly rule to avoid.
Does the whole of basic strategy have to be memorised?
Not at once. Four decisions cover most of the loss: stand on 17 or more, stand on 13 to 16 against a dealer 2 to 6, always split aces and eights, and never take insurance.
Is card counting against the law?
Counting is not illegal, as it uses nothing but the player's memory, but a casino may refuse service to anyone using it. At online tables shuffled every round it confers no advantage at all.