Decision Library

Pair of 9s vs 10

Pair of 9s vs dealer 10 · six decks · dealer stands on soft 17 · double after split allowed

Correct play

Stand

The best you can do is hold the loss to -0.172 per unit, and standing beats splitting by 0.121 per unit.

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Deals a pair of 9s against a dealer 10 in the trainer, graded live.

Expected value of every option

Per unit bet, six decks, dealer stands on soft 17, computed by the engine.

OptionEV / unitvs. best
StandBest-0.172
Split-0.292-0.121
Surrender-0.500-0.328
Hit-0.644-0.473
Double-1.288-1.117
23.1%
Dealer busts showing 10
76.7%
You bust if you hit

Why standing

With a pair of 9s you already hold a total the dealer has to beat, and the 10 is weak enough that letting the dealer draw is better than risking your own hand. The dealer busts 23.1% of the time showing a 10, while hitting would bust you 76.7% of the time.

Standing is worth -0.172 per unit; the closest alternative, splitting, comes in at -0.292. That 0.121 gap is the price of taking an unnecessary card.

The common mistake

Players hit a pair of 9s out of fear of the dealer's 10, but the 10 is exactly why you stand. Hitting costs 0.473 per unit versus the correct standing. Over a few hundred of these hands, that is real money handed back.

How rules change the play

Same hand, different table conditions. The correct play holds unless noted.

Table conditionCorrect play
6 decks, stands soft 17 (baseline)Stand
6 decks, hits soft 17Stand
Single deck, stands soft 17Stand
Double deck, stands soft 17Stand
No surrender offeredStand

The play is stable: stand is correct across deck counts, the soft-17 rule, and whether or not surrender is offered.

Related decisions

See the full decision chart →

Strategy and expected values from a combinatorial engine validated against Wizard of Odds.