Decision Library
Hard 15 vs dealer Ace · six decks · dealer stands on soft 17 · double after split allowed
Correct play
HitThe best you can do is hold the loss to -0.482 per unit, and hitting beats surrendering by 0.018 per unit.
Deals a hard 15 against a dealer ace in the trainer, graded live.
Per unit bet, six decks, dealer stands on soft 17, computed by the engine.
| Option | EV / unit | vs. best |
|---|---|---|
| HitBest | -0.482 | — |
| Surrender | -0.500 | -0.018 |
| Stand | -0.664 | -0.182 |
| Double | -0.986 | -0.504 |
Hard 15 is too low to leave alone against a ace. Standing surrenders the hand to a dealer who reaches a pat total most of the time, so you take the card. Your bust risk on the hit is 54.0%, and against this upcard that risk is worth accepting.
Hitting returns -0.482 per unit versus -0.664 for standing, a +0.182 swing in favor of taking the card.
It is tempting to stand on 15 and hope the dealer busts, but against a ace that hope is too thin. Standing costs 0.182 per unit versus the correct hitting. Over a few hundred of these hands, that is real money handed back.
Same hand, different table conditions. The correct play holds unless noted.
| Table condition | Correct play |
|---|---|
| 6 decks, stands soft 17 (baseline) | Hit |
| 6 decks, hits soft 17 | Surrender changes |
| Single deck, stands soft 17 | Hit |
| Double deck, stands soft 17 | Hit |
| No surrender offered | Hit |
The correct play changes under: 6 decks, hits soft 17. Everywhere else, hit holds. Use the row that matches your table.
Strategy and expected values from a combinatorial engine validated against Wizard of Odds.