Every upcard, computed
These come from playing the dealer's hand out by recursion over every possible draw, under both the stand-on-soft-17 and hit-soft-17 rules.
| Dealer upcard | Bust chance (S17) | Bust chance (H17) | Reaches 17-21 |
|---|---|---|---|
| 2 | 35.36% | 35.67% | 64.64% |
| 3 | 37.39% | 37.67% | 62.61% |
| 4 | 39.45% | 39.71% | 60.55% |
| 5 | 41.64% | 41.77% | 58.36% |
| 6 | 42.32% | 43.95% | 57.68% |
| 7 | 26.23% | 26.23% | 73.77% |
| 8 | 24.47% | 24.47% | 75.53% |
| 9 | 22.84% | 22.84% | 77.16% |
| 10 | 22.98% | 22.98% | 77.02% |
| Ace | 16.65% | 20.07% | 83.35% |
The cliff between 6 and 7
Read down the S17 column and one gap dominates everything. A dealer showing 6 busts 42.32% of the time. A dealer showing 7 busts 26.23% of the time. One rank apart, and the bust chance falls by more than a third.
The reason is the ten-count. Cards 2 through 6 force the dealer to draw to a stiff total, and a ten-valued card, which is four ranks out of thirteen, breaks it. From a 7 the dealer reaches 17 with a single ten and stops safely.
Why this is the whole of basic strategy
This table explains the part of the chart players resist most: standing on a hard 15 or 16 against a dealer 4, 5 or 6.
Standing on 16 feels passive because 16 rarely wins on its own. But against a 6, the dealer hands you the pot 42.32% of the time by busting, while hitting a 16 busts you on any card above a five. You are not betting on your hand. You are betting on theirs.
The mirror holds too. Against a 7 or higher the dealer busts under a third of the time and will usually make 17 or better, so a 16 that stands almost always loses. That is why the chart says hit.
H17 in the same table
Compare the two columns. Hitting soft 17 raises the dealer's bust chance on some upcards, which sounds good for the player and is not: the dealer also improves a hand that would otherwise have stopped at 17. Net, it costs the player +0.22 percentage points, as covered on our H17 against S17 page.
The full decision table built on these numbers is on our basic strategy page.
Frequently Asked Questions
- Which dealer upcard is worst for the dealer?
- A 6, which busts 42.32% of the time under S17. The 4, 5 and 6 are the classic bust cards.
- How often does a dealer bust showing an ace?
- 16.65% under S17. An ace is the strongest upcard in the game.
- Why do I stand on 16 against a 6?
- Because the dealer busts 42.32% of the time and hitting a 16 busts you on any card above a five. You are betting on the dealer's hand, not your own.
- Why is there such a jump between 6 and 7?
- From 2 to 6 the dealer must draw to a stiff total that a ten-valued card breaks. From 7 a single ten makes a safe 17.
Every figure on this page is computed by an expected-value engine that plays the game out: it derives the dealer's final-total distribution by recursion, evaluates standing, hitting, doubling and splitting at each decision, and takes the best. Rule costs are measured by re-running the whole calculation with the rule changed, not by quoting a published delta. The model assumes independent card draws, which sits a few hundredths of a percent from an exact shoe analysis; the rule differences it produces match published values. Rules vary by table, so read the felt.