Master blackjack with interactive strategy charts, probability visualizations, and expert insights. Learn when to hit, stand, double, or split for every hand.
These charts show the mathematically optimal play for every hand. Memorize them to minimize the house edge to around 0.5%. These charts assume 4 to 8 decks, the dealer hits soft 17, and doubling after a split is allowed.
Hands without an Ace counted as 11
Hands with an Ace counted as 11
When to split pairs vs dealer upcard
You have a strong enough hand. Let the dealer risk busting.
Your hand is weak. Take another card to improve.
Favorable situation. Double your bet and take one card.
Understanding the math behind blackjack helps you make better decisions and trust the strategy.
The dealer's visible card significantly affects their likelihood of busting. Low cards (2-6) are "weak" because the dealer must hit to 17, often leading to busts.
Dealer busts 35-43% of the time. These are opportunities to stand on lower totals.
Dealer busts only 17-26% of the time. You need to improve your hand to compete.
Your risk of busting increases dramatically with higher hand values. This is why standing on stiff hands (12-16) is sometimes correct.
Bust probability is 31-39%. Usually worth the risk against strong dealer cards.
Bust probability exceeds 69%. Almost always stand on 17 or higher.
0.5%
Perfect Basic Strategy
1-2%
Average Player
4-5%
Poor Strategy
The "Illustrious 18" and other key deviations from basic strategy based on the true count.
Educational Purposes Only
Card counting is not illegal, but casinos may ask you to leave if they suspect you're counting. These deviations assume you know the true count. Always gamble responsibly.
+1
2, 3, 4, 5, 6
Low cards
0
7, 8, 9
Neutral
-1
10, J, Q, K, A
High cards
True Count = Running Count ÷ Decks Remaining
Avoid these frequent errors that cost players money. Each mistake increases the house edge.
Mistakes Cost Money
Perfect basic strategy gives a house edge of ~0.5%. Common mistakes can increase it to 2-5% or more. Learn these pitfalls to protect your bankroll.
You have 12, dealer shows 2 or 3
Cost
-$0.25 per $10 bet
Wrong Play
Stand
Correct Play
Hit
Many players think any stiff hand should stand against weak upcards. But 12 is special - the dealer's 2-3 aren't weak enough, and you have low bust risk.
You have 8,8 vs dealer 9, 10, or A
Cost
-$0.45 per $10 bet
Wrong Play
Hit or Stand
Correct Play
Split
16 is the worst hand in blackjack. Two chances to make 18 is better than one terrible hand, even against strong upcards.
You have A,6 (soft 17)
Cost
-$0.35 per $10 bet
Wrong Play
Stand
Correct Play
Hit
You can't bust! Hitting gives you a chance to improve to 18-21. Standing on soft 17 is one of the biggest mistakes beginners make.
You have 11 vs any dealer card
Cost
-$0.50 per $10 bet
Wrong Play
Hit
Correct Play
Double
11 is the best doubling hand. You have the highest probability of hitting 21, and even 20 or 19 are strong. Always double (except vs A in some rules).
Dealer shows Ace
Cost
-$0.77 per $10 insurance bet
Wrong Play
Take Insurance
Correct Play
Never Take Insurance
Insurance has a 7.7% house edge - one of the worst bets in the casino. Unless you're counting cards and the count is +3 or higher, never take it.
You have hard 17, 18, 19, or 20
Cost
-$1.20+ per $10 bet
Wrong Play
Hit
Correct Play
Stand
Some players hit 17 against a dealer 10 or Ace. This is a huge mistake - you'll bust more often than improve.
You have 10,10 (any dealer card)
Cost
-$0.55 per $10 bet
Wrong Play
Split
Correct Play
Stand
20 is the second-best hand! Why risk turning a near-certain winner into two uncertain hands? (Exception: card counters at TC +5)
Soft 15-18 vs dealer 5 or 6
Cost
-$0.30 per $10 bet
Wrong Play
Hit
Correct Play
Double
Dealer 5-6 are the weakest upcards (42% bust rate). Soft hands can't bust on one card. Double to maximize value.
Any hand
Cost
Variable
Wrong Play
Going with your gut
Correct Play
Follow basic strategy
Basic strategy is mathematically optimal. Every deviation increases the house edge. Trust the math, not feelings.
16 vs 9-A, 15 vs 10
Cost
-$0.20 per wrong decision
Wrong Play
Random surrender decisions
Correct Play
Surrender 16 vs 9/10/A, 15 vs 10
If available, surrender saves money on specific losing hands. But over-surrendering gives up EV on playable hands.
Use our calculator to verify the optimal play for any hand in real-time.
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