Blackjack · 20 rounds · Sep 25, 2026, 8:38 PM UTC
Round 20
Dealer
Round 20 result · Dealer 24
Claude Haiku 4.5
Hand 1 · 20 soft · bet 10
Win +10
With a hard 12 against dealer's 4 (a bust card), standing is optimal. The dealer has a high probability of busting, and hitting a 12 risks drawing 9-K (10 cards) and busting ourselves.
With 12 against dealer's 6 (a bust card), standing is optimal. Dealer has ~42% bust probability, and hitting 12 creates excessive bust risk (hitting any 10-value card busts immediately); basic strategy calls for standing in this spot.
With a soft 13 (Ace-2) against dealer's 7, hitting is the optimal play. The dealer's 7 is a strong upcard, so we need to improve our hand. Since we have an Ace counting as 11, we can safely hit without busting on most cards, and we're in a weak position that requires aggressive improvement.
With a soft 16 (Ace-2-3) against dealer's 7, hitting gives significant upside: reaching 17-21 without bust risk while the dealer faces a strong upcard. Standing at 16 loses to most dealer outcomes.
With a hard 16 against dealer's 7, hitting is the optimal play according to basic strategy. The dealer's 7 is a strong upcard (likely to make 17+), so standing on 16 loses most of the time. Hitting gives a chance to improve to 17 or better, and the bust risk is acceptable given the poor win probability of standing.
With 14 against dealer's 7, hitting is optimal. The dealer has a strong upcard (7 makes 17 most likely), so I need to improve my hand. Doubling 14 is disadvantageous as it locks in more chips with a weak total.
With 12 against dealer's 5 (a weak upcard), standing is correct basic strategy. The dealer has a high bust probability, and hitting 12 risks busting while the dealer is likely to go over 17.
With 12 against dealer's 5 (a bust card), standing is optimal. The dealer has a high bust probability from 5 upcard, and hitting 12 risks busting immediately with many cards (K, Q, J, 10 all bust). Basic strategy recommends standing on 12 vs 5.
With 11 against dealer's weak 5, doubling down is the mathematically optimal play. The dealer's upcard is a bust card, and 11 gives excellent potential for reaching 21.
With a hard 8 against dealer's 7, hitting is standard basic strategy. The dealer's 7 is a strong card, so we need to improve our hand. Doubling 8 is too aggressive here; we're unlikely to reach 18-20 with a single card.
With a hard 15 against dealer's 7 (a strong upcard), hitting is the statistically correct play. Dealer 7 makes a stand at 15 too risky; the hit improves chances of reaching 17-21 or busting less favorably than standing would.
Hand total is 19, which is a strong hand. Dealer upcard is 7, and dealer must hit on soft 17 or lower, making 19 a winning hand in most scenarios. Standing is the correct play.
With 15 against dealer's 3 (bust card), standing is optimal. The dealer is likely to bust with a 3 showing, and hitting 15 risks busting immediately (any 7+ busts). Basic strategy favors standing here.
With a hard 16 against dealer's 7, hitting has a high bust probability (~62%) while standing gives the dealer a chance to bust. Dealer 7 is moderately strong but not a dominant upcard; doubling would risk more chips with unfavorable odds.
With a hard 20 against dealer's King, standing is correct. A 20 is a very strong hand that wins against most dealer outcomes, and the risk of busting on a hit far outweighs any potential gain.
With a pair of Aces against dealer's 2, splitting is the optimal play. This gives two chances to hit 21 and maximizes expected value against the dealer's weak upcard.
Hard 17 vs dealer 7 is a classic stand situation. Doubling risks busting while standing gives a reasonable chance to win since dealer must play to 17+ and will bust on many completions.
With a hard 18 against the dealer's 9, standing is the mathematically optimal play. A hard 18 beats most dealer hands except 19, 20, or 21, and hitting risks busting or receiving a card that doesn't improve the hand.
With a hard 6 against dealer's Ace, hitting is optimal. The dealer likely has 17+ (Ace up), so I need to improve my hand. Doubling would be too risky with such a weak total.
With a hard 16 against dealer's Ace, hitting is the statistically superior option. The dealer's Ace is the strongest upcard, and standing on 16 gives an extremely poor win probability. Hitting offers a chance to improve to 17 or better, though it carries bust risk.
I have 18 (2-4-Q-2), which is a strong hand. The dealer shows an Ace, which could be a blackjack or any value from 11 to 21. Standing on 18 is correct strategy as hitting risks busting, and my hand is competitive against most dealer outcomes.
With a hard 11 against dealer's 8, doubling down is mathematically optimal. This is one of the strongest doubling opportunities in blackjack, as we have maximum upside potential (reaching 21) while the dealer's 8 is a moderately weak card.
With 16 against dealer's 6, standing is optimal. The dealer's weak upcard (6) likely busts on a stiff hand, so doubling 16 is mathematically unfavorable despite the temptation; hitting risks busting while the dealer has higher bust probability.
Hard 12 vs dealer 9 is a classic stiff hand situation. Hitting risks busting (any card 10+ busts), while standing avoids immediate bust. Basic strategy dictates standing on hard 12 against dealer 9 to minimize losses.
I have a soft 20 (Ace-9), which is an excellent hand. Doubling down is unnecessary since hitting would likely bust or result in 21 at best, while standing guarantees a strong outcome against the dealer's Queen upcard.
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Session result: -25 chips over 20 rounds
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