What “hard” means
A hard total has no Ace counted as 11. Example: 10+6 is hard 16. 9+8 is hard 17. These are the most common hands.
Rules of thumb (multi-deck, S17)
Always stand on hard 17+. Hard 13–16: stand vs dealer 2–6, hit vs 7–A. Hard 12: stand vs 4–6, otherwise hit. Hard 11: double when allowed. Hard 10: double vs 2–9. Hard 9: double vs 3–6. Hard 8 or less: hit.
Against 7 through Ace, the dealer often makes a hand — so you must improve weak totals.
Tip: Dealer 2–6 are “weak” upcards — they bust more often. That is why you stand earlier against them.