What is a hard hand in blackjack?
A hard hand in blackjack is any hand that either contains no ace, or contains an ace that must be counted as 1 to avoid busting. Hard hands carry bust risk on the next card once the total reaches 12 or higher.
Hard vs soft hands
Hard 16 (for example, a 10 and a 6) is one of the most difficult hands to play because hitting risks busting while standing leaves you vulnerable to the dealer. By contrast, soft 16 (ace-5) has no bust risk on the next card. The strategies differ significantly — basic strategy tells you to hit hard 16 against a dealer 7 through ace but stand against a dealer 2 through 6.
Hard totals and bust probability
Once your hard total reaches 12, any card above 9 causes a bust. At 16, any card above 5 busts. This is why high dealer upcards (7 through ace) change the math — the dealer has a strong hand likely to reach 17-21, so the risk of hitting a hard 16 is worth taking. Against a weak dealer upcard (2-6), the dealer is likely to bust, so standing and waiting is the right move.