Blackjack · 20 rounds · Sep 25, 2026, 8:38 PM UTC
Round 20
Dealer
Round 20 result · Dealer 17
Claude Haiku 4.5
Hand 1 · 18 · bet 10
Win +10
With a soft 16 (Ace-5) against dealer's 6, doubling down is the mathematically optimal play. The dealer's 6 is a bust card, and doubling maximizes expected value by forcing a single additional card while dealer is vulnerable.
With a hard 17 against dealer's 7, standing is the optimal play. Hitting risks busting (any card 5 or higher busts), while the dealer's 7 upcard suggests they may bust with a 10-value hole card. Basic strategy recommends standing on hard 17 regardless of doubling availability.
With a hard 15 against dealer's 6 (weak upcard), standing is optimal. Basic strategy dictates standing on 15 vs 6 since the dealer has a high bust probability (42%) and doubling or hitting would be worse in expectation.
With a hard 15 against dealer's 10, standing is the mathematically optimal play. Hitting risks busting (any card 7 or higher busts), while standing gives the best probability of winning given the unfavorable situation.
With 12 total against dealer's 2 (bust card), standing is correct basic strategy. The dealer is likely to bust, and hitting 12 risks busting myself (any 10-value card busts).
With hard 13 versus dealer's Jack (value 10), hitting is the mathematically correct play. Doubling down would commit more chips to a weak hand, and standing gives the dealer a strong winning position (dealer likely has 10 or face card). Hit to improve the hand.
With a hard 6 against dealer's 10, hitting is the optimal play. Doubling down on such a weak hand is too risky, and standing gives the dealer a strong advantage. Hit to improve the hand.
With a hard 9 against dealer's 10, hitting is the mathematically correct play. A 9 total is very weak, and we need to improve; the probability of busting is low (only 4-card 10+ would bust), while hitting gives us a good chance to reach 17-21.
With a hard 17 against dealer's 10, standing is the correct basic strategy play. The dealer's 10 upcard is strong, but hitting risks busting with a 17 already formed.
With a pair of 2s against the dealer's Ace, splitting is the optimal play. This gives me two chances to develop strong hands, as both resulting hands can reach 12+ with a single card. The dealer showing an Ace is a weak up card for the player, making the split strategy mathematically superior to hitting or standing on 4.
With 12 against dealer's Ace, I'm in a difficult spot. The dealer shows Ace (likely 11 or 21). Doubling would risk 20 chips total for an uncertain payoff. Hitting gives me a chance to improve to 17+ or bust, but it's the better expected value play here than standing on a stiff 12.
With a hard 12 against dealer's Ace, standing is optimal. The dealer shows Ace and will check for blackjack; if no blackjack, dealer stands on 17+ and will likely bust only on stiff cards (not an Ace). Hitting 12 risks busting (any card 10+ busts); standing gives the best chance to win or push if dealer busts.
With a hard 19 against dealer's King (10-value), standing is optimal. My hand is strong and unlikely to improve; doubling risks busting or pushing, while hitting could result in bust. The dealer likely has 10 or 20, making 19 a competitive position best preserved.
With a pair of 3s totaling 6 against dealer's 7, splitting is optimal. Each 3 gives a starting point for potential 13-value hands, and split hands provide more opportunities to reach 17-21 than standing on 6 or hitting once on 6.
With 3-5=8 against dealer's 7, hitting is standard basic strategy. The 7 is a strong dealer card (likely 17), so I need to improve my weak 8. Doubling would be too aggressive with such a poor starting hand.
Hand 0 totals 17 against dealer's 7. Standing on 17 is the correct basic strategy play; hitting risks busting (any card 5 or higher) while the dealer's 7 is moderately strong but not dominant.
With a pair of 3s (total 6) against dealer's 7, hitting is the mathematically sound play. A hard 6 is a weak hand that needs improvement, and splitting 3s against a 7 is less favorable than hitting toward a stronger total.
Current hand is a soft 17 (3-3-A), which is a strong defensive position against dealer's 7 upcard. Hitting risks busting or landing on a stiff hand, while standing gives the dealer the pressure to act first and potentially bust.
With a hard 5 against dealer's 3 (a weak upcard), hitting is standard basic strategy. Doubling down on 5 is too risky and standing leaves me too vulnerable. The dealer's 3 is bust-prone, but I need to build my hand first.
With a hard 13 against dealer's 3 (a weak upcard), basic strategy dictates hitting. The dealer's 3 gives them a reasonable bust probability, but my 13 is too weak to stand on; I need to improve my hand.
With a hard total of 18 against the dealer's 3, standing is optimal. The dealer has a weak upcard and is likely to bust, while hitting risks busting or getting a lower total.
Holding soft 17 (Ace-6) against dealer's 9 upcard. Basic strategy dictates standing on soft 17 against a dealer 9, since hitting is unlikely to improve the hand significantly and risks busting on a 5 or higher.
With a hard 11 against dealer's 10-value card, doubling down is the mathematically optimal play. This hand has excellent potential to reach 21 with a single card, and the cost is minimal given the high probability of improvement.
With 16 against dealer's 5 (a weak upcard), standing is optimal. The dealer has a high bust probability, and hitting my hard 16 risks busting. Basic strategy dictates standing in this spot.
With 14 against dealer's 8, hitting is the statistically optimal play. The dealer likely has 18 (8+10), so I need to improve. Doubling would risk 20 chips for marginal gain when hitting gives better odds of reaching 17+ without committing extra chips.
With a hard 17 against dealer's 10, standing is the correct basic strategy play. Hitting risks busting (any card 5 or higher busts), while doubling with only 17 is mathematically unfavorable against a strong dealer upcard.
With a hard 17 against dealer's 4 (bust card), standing is optimal. The dealer busts approximately 40% of the time from this upcard, and hitting a 17 risks busting while doubling would risk more chips for minimal expected gain.
I have a hard 18 against the dealer's King upcard. Standing is the optimal play here since hitting risks busting while 18 beats most dealer outcomes; doubling would increase variance unnecessarily when the hand is already strong.
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Session result: -55 chips over 20 rounds
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