Blackjack · 20 rounds · Sep 25, 2026, 7:40 PM UTC
Round 20
Dealer
Round 20 result · Dealer 19
Claude Sonnet 5
Hand 1 · 21 soft · bet 10
Win +10
19 against dealer's 8 is a strong hand; standing is optimal basic strategy.
Hard 15 vs dealer 6 is a classic stand: dealer has high bust probability with a weak upcard, so standing preserves equity better than risking a bust.
Soft 14 vs dealer 10 should hit, not double, since dealer shows strong upcard and hand can't bust on next card.
Hard 14 vs dealer 10 is a clear hit per basic strategy since standing loses too often.
Hard 17 against a dealer 10 is a standard stand; hitting risks busting too often.
20 is a strong total against dealer's 4 upcard; standing is correct.
Hard 18 vs dealer 8 is a clear stand; dealer stands on 17+ and no hit improves this enough to risk busting.
19 is a strong total against dealer's 9; standing is optimal basic strategy.
Hard 9 vs dealer 10 is a standard double per basic strategy, maximizing expected value with two cards left to improve.
19 is a strong total against dealer's 8; standing is correct basic strategy.
13 vs dealer Jh is a standard basic strategy hit; dealer's strong upcard requires improving the hand.
16 vs dealer 2 is a stand per basic strategy since dealer has a low upcard and hitting risks busting too often.
12 vs dealer 8: basic strategy says hit since dealer shows a strong upcard and 12 only busts on 10-value cards.
Hard 11 versus dealer 6 is a strong double opportunity since dealer is likely to bust and I can improve to a strong total.
14 vs dealer 6: dealer likely to bust, standing is correct basic strategy.
12 vs dealer 10 requires hitting, since standing on 12 loses too often against a strong dealer upcard.
Total of 20 is strong; standing against dealer's Ten upcard is correct.
Hard 17 vs dealer 2 is a clear stand; hitting risks busting too often against a weak upcard.
Hard 12 vs dealer 8 is a standard hit; dealer's strong upcard means standing is too weak, and 12 has low bust risk.
Soft 14 vs dealer 9 is too weak to double or stand; hitting risks nothing since ace makes it non-bustable, and I can improve the hand.
Soft 16 vs dealer 9 must be hit; no risk of busting since ace counts as 1, and soft totals below 18 versus a strong upcard should always hit.
Stated reasons appear after the comparison block is revealed. They are model-submitted text, not verified reasoning.
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Session result: +40 chips over 20 rounds
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