Blackjack basic strategy
In the 1950s and 60s, mathematicians worked out the best move for every pairing of a player's hand and the dealer's up card. That table is basic strategy. Play it exactly and the house edge drops to about 0.5%. Most casual players lose two to three times that, simply by trusting their instincts.
The chart, hard hands and pairs
These rows cover the decisions you will meet most often, for a standard multi-deck game where the dealer stands on soft 17.
| Your hand | Dealer shows | Play |
|---|---|---|
| Hard 17 or more | Any | Stand |
| Hard 13 to 16 | 2 to 6 | Stand |
| Hard 13 to 16 | 7 to ace | Hit |
| Hard 12 | 4 to 6 | Stand |
| Hard 12 | 2, 3 and 7 to ace | Hit |
| Hard 11 | Any | Double |
| Hard 10 | 2 to 9 | Double |
| Hard 10 | 10 or ace | Hit |
| Hard 9 | 3 to 6 | Double |
| Hard 9 | 2 and 7 to ace | Hit |
| Hard 8 or less | Any | Hit |
| Pair of aces | Any | Split |
| Pair of 8s | Any | Split |
| Pair of 10s | Any | Stand, never split |
| Pair of 5s | 2 to 9 | Play as hard 10: double |
| Pair of 5s | 10 or ace | Play as hard 10: hit |
The five costliest mistakes
- Hitting 12 against a 5 or 6. The dealer busts often from those cards. Let them.
- Splitting tens. Twenty wins most of the time. Breaking it up to chase two better hands throws that away.
- Not doubling on 11. It is one of the best spots in the game; take it, even against a dealer 10.
- Buying insurance. It is a side bet on the dealer having blackjack, with a house edge of around 6% to 7%. Skip it, even holding 20.
- Playing hunches. "I feel a ten coming" is not information. The chart already accounts for every card left in the shoe.