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
Loss -10
Hand 2 · 11 soft · bet 10
Loss -10
With a hard 19 against dealer's 2, standing is optimal. The dealer's weak upcard doesn't justify the risk of busting by hitting, and doubling would be inefficient given the strong hand value.
With a hard 10 against dealer's King (10-value card), doubling down is the mathematically optimal play. A 10-total hand has favorable prospects for improvement with a single card, and doubling maximizes expected value in this position.
With 13 against dealer's 3 (weak upcard), hitting is standard basic strategy. The dealer's 3 is a bust card, but my stiff hand needs improvement; I'll hit to try reaching 17+ while the dealer is vulnerable.
With a hard 12 against the dealer's weak 2, hitting is the optimal play. A 12 is a stiff hand that easily busts on many cards, but the dealer's 2 is a weak upcard that often leads to dealer busts, making it incorrect to stand and let the dealer play out their hand.
With 14 against dealer's 2, hitting is correct basic strategy. The dealer's weak upcard (2) means they bust frequently, but my 14 is too weak to stand; I need to improve or risk losing. Hitting gives me the best expected value.
With 14 against dealer's 7, hitting is correct basic strategy. The dealer's 7 is a strong card (likely 17), so I need to improve my hand. Standing would give me a weak hand against the dealer's likely strong total.
Split Aces against dealer's 10-value card. This is a fundamental strategy play that gives me two chances to hit 21 instead of being stuck with a soft 12. Even with the restriction of one card per Ace, splitting maximizes expected value against a strong dealer upcard.
With a hard 11 against dealer's King (10-value), doubling down is the optimal play. This hand has strong potential to improve to 21 or a strong total, and doubling maximizes expected value against a dealer's strong upcard.
Soft 16 (Ace-5) versus dealer Ten is a classic double-down situation. Doubling maximizes expected value when the dealer is weak-ish and we have a soft hand that benefits from exactly one card.
With a soft 18 (Ace-7) against the dealer's 8, standing is the optimal play. This hand wins against dealer busts and pushes on 18, while hitting risks busting or reducing the hand value.
With a hard 11 against dealer's Queen, doubling down is the optimal play. This hand has strong potential to reach 21, and the dealer's 10-value card makes this an aggressive but mathematically correct decision to maximize expected value.
With 13 against dealer's Ace, hitting is correct. The dealer likely has 21 (Ace upcard with dealer peeking rules), making standing at 13 a losing position. Hitting gives a chance to improve to 17+ or bust, but standing guarantees a loss.
With a hard 5 against dealer's 4, hitting is the correct basic strategy play. The dealer's 4 is a weak upcard but my 5 is too low to stand on; I need to improve my hand while the dealer is in a bust-prone situation.
With a hard 10 against dealer's 4, hitting is optimal. The dealer's weak upcard suggests standing, but my 10 is too weak to stand on; I need to improve my hand significantly. Hitting gives me strong winning chances (hitting to 20+ or 21 is highly likely with multiple cards that help)
With a hard 12 against dealer's 4 (weak upcard), basic strategy dictates hitting. The dealer's 4 is a bust card but our 12 is still vulnerable; hitting gives us a chance to improve while the dealer remains in a difficult position.
Player has a hard total of 20 (3+2+5+2+8), which is a very strong hand. With dealer showing 4 (bust card), standing is optimal to avoid busting and let the dealer bust.
With a hard 11 against dealer's 10, doubling down is the mathematically optimal play. An 11 is the best hand to double on since any non-bust card significantly improves the total, while the dealer's 10 is a strong but not unbeatable upcard.
With 12 against dealer's King (10-value), hitting is correct basic strategy. The hand is weak and standing risks losing to a likely 17-20, while hitting gives a chance to improve without busting.
With a hard 17 against dealer's Jack (10-value card), standing is optimal. The dealer's upcard suggests a strong hand, and hitting risks busting (any card 5+ busts). Basic strategy recommends standing on hard 17 regardless of dealer upcard.
I have 17 (7+K) against dealer's K upcard. Standing is the correct play since hitting a hard 17 is mathematically poor (likely busting), and doubling on 17 is a weak move that only increases losses. The dealer must hit on soft totals under 17, so standing gives me the best chance to win or push.
With a hard 20 against the dealer's 2 (weak upcard), standing is optimal. The probability of improving with a hit is negligible while the risk of busting is substantial. Doubling would be greedy and unnecessary given the strong hand.
With a hard 18 against dealer's Queen (10-value), standing is optimal. The dealer's upcard represents strength, and hitting risks busting or getting a worse outcome, while 18 is a strong hand that wins or pushes in most dealer outcomes.
Splitting 4s against dealer's 4 (a weak upcard) allows me to play two hands with better potential value. This is a standard basic strategy play that improves my expected value by giving me two chances to make stronger totals from a low starting position.
Hand total of 14 against dealer's 4 (weak upcard). Dealer busts ~42% of the time on 4. Doubling risks pushing 24+ chips when standing keeps the current bet intact. Standing maximizes expected value here.
With a soft 15 (Ace-4) against dealer's 4, standing is optimal. The dealer is in a weak position and likely to bust, so doubling risks a net loss. A hit risks reaching 25+ on soft hands or improving minimally.
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Session result: -100 chips over 20 rounds
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