The dealer’s up-card is the single most important piece of information you get before deciding how to play a blackjack hand. It tells you, roughly, how likely the dealer is to go over 21 and hand you the pot without a fight. “Dealer bust probability” is simply the chance the dealer’s final total ends up above 21 for each card they show. These odds are fixed by the dealer’s rigid drawing rules, so they can be measured precisely — and once you know them, a lot of basic strategy stops feeling arbitrary. This guide breaks down the bust odds for every dealer up-card, explains why some cards are so much weaker than others, and shows what the numbers mean for your own decisions. For the companion view of how often you bust, see our overview of player and dealer bust probability.
What “dealer bust” actually means
A bust is any hand whose total goes over 21. When the dealer busts, every player still in the hand wins automatically, no matter what their own total is. That is why the dealer’s up-card matters so much: the weaker the dealer’s card, the more often you win simply by not busting first.
Unlike a player, the dealer has no choices. In almost every casino the dealer must keep drawing until reaching a hard total of 17 or more, then stop. That fixed rule is the reason dealer bust odds are so stable and predictable — the dealer cannot “play it safe” with a weak card or chase a better hand with a strong one. (If you need a refresher on exactly when the dealer draws, see our guide to blackjack dealer rules and soft 17.)
Dealer bust probability by up-card
The table below shows how often the dealer busts for each up-card in a standard multi-deck game where the dealer stands on all 17s (known as S17). The figures are long-run averages derived from the full set of dealer drawing outcomes; your single hand will of course land anywhere, but across thousands of rounds these percentages hold.
Dealer Bust Odds by Up-Card
| Dealer up-card | Bust probability (S17) | Dealer strength |
|---|---|---|
| 2 | ~35.3% | Weak |
| 3 | ~37.6% | Weak |
| 4 | ~40.3% | Very weak |
| 5 | ~42.9% | Weakest |
| 6 | ~42.1% | Very weak |
| 7 | ~26.0% | Strong |
| 8 | ~23.9% | Strong |
| 9 | ~23.3% | Strong |
| 10 / J / Q / K | ~21.2% | Very strong |
| Ace | ~11.7% | Strongest |
| Average | ~28% | — |
A few patterns jump out. The dealer busts most often with a 5 (about 42.9%) and a 6 (about 42.1%) — close to a coin flip. From a 7 upward the bust rate roughly halves. Averaged across every up-card, the dealer busts only about 28% of the time, which is a useful reality check: most of the time the dealer makes a hand, so the up-card chart tells you when the odds have tilted your way, not that the dealer is usually in trouble.
Why 2 through 6 are the dealer’s weak cards
Cards from 2 to 6 are called the dealer’s “stiff” cards because they often lead to a stiff hand — a hard total of 12 to 16 that is too low to keep but dangerous to hit. With a small up-card the dealer is frequently forced to draw to a total like 13, 14, 15 or 16, and any 10-value card (there are sixteen of them in each deck) then busts the hand.
- Up-cards 4, 5 and 6 are the weakest of all, with bust rates around 40–43%. These are the cards you most want to see the dealer turn over.
- Up-cards 2 and 3 are weak but noticeably less so (about 35–38%), because the dealer has more room to draw a middle card and still reach 17–21 without going over.
One common myth is that 6 is always the dealer’s worst card. In most rule sets the 5 edges it out by a fraction, and a 2 or 3 is a good deal safer for the dealer than people assume. The broad takeaway is reliable, though: any 2–6 is a card you want the dealer stuck with.
Why 7 through Ace are strong cards
From 7 upward the picture flips. A 7, 8 or 9 lets the dealer reach a pat total (17–20) in a single draw a large share of the time, so the bust rate falls to roughly 23–26%.
The two strongest up-cards are the 10-value card and the Ace:
- A ten (10, J, Q or K) busts only about 21% of the time, because one more card so often completes a 17–21.
- An Ace shows the lowest bust rate of all — under 12% in games where the dealer checks for blackjack first. The reason is twofold: an ace creates flexible soft hands that can absorb a big card without busting, and in North American rules any ace that would have made a natural blackjack is already removed from these figures before play continues. That is why the Ace number looks surprisingly low compared with a 10.
When the dealer shows a 7 or higher, you generally need to build a strong hand yourself rather than wait for a bust — which is exactly why knowing when to hit or stand depends so heavily on the up-card.
How the dealer’s rules shift the odds (S17 vs H17)
The single biggest rule variation is whether the dealer stands on soft 17 (S17) or hits soft 17 (H17). A soft 17 is a hand of ace-plus-six, where the ace still counts as 11. Under H17 the dealer takes one more card on that total instead of stopping.
Hitting soft 17 slightly raises the dealer’s bust rate on some up-cards — most noticeably the Ace and the 7 — but it also lets the dealer improve a weak 17 into an 18, 19, 20 or 21 more often. The net effect favours the house: an H17 rule adds roughly 0.2% to the house edge compared with S17. So a higher dealer bust rate is not automatically good news for players; the extra made hands outweigh the extra busts. Where you have the choice, an S17 table is the better one.
What dealer bust odds mean for your play
Dealer bust probability is the engine behind much of basic strategy. Because the dealer busts far more often with 2–6, you can afford to play cautiously against those cards; against 7–Ace you have to take more risk to compete.
- Stand on stiff totals against weak cards. With a hard 12–16 against a dealer 4, 5 or 6, basic strategy usually says stand. You expect to lose if you draw and bust yourself, so you let the dealer take the risk instead.
- Hit stiff totals against strong cards. The same hard 12–16 against a 7, 8, 9, 10 or Ace is a hit, because standing hands the dealer an easy win most of the time.
- Double and split more against 4–6. The dealer’s high bust rate is why you double down and split pairs more aggressively against those cards — you are putting extra money out when the dealer is most likely to fail.
These dealer odds are already baked into a blackjack basic strategy chart, so you do not need to memorise the percentages to play correctly. Understanding them simply helps the chart make sense. For the wider maths of how all of this feeds the blackjack odds and house edge, see our odds overview.
Common misconceptions
- “The dealer busts about half the time.” No — only about 28% overall. The 40%+ figures apply only to the weakest up-cards.
- “A 6 is always the dealer’s worst card.” The 5 is usually marginally worse, and the gap between any 4, 5 or 6 is small.
- “More dealer busts always help me.” Under H17 the dealer busts a little more but also makes stronger hands, and the house edge still rises.
- “I should copy the dealer and hit to 17.” The dealer acts last, so “mimic the dealer” actually costs you because you bust first and lose immediately — one of the most expensive habits in the game.
Key Points
- The dealer busts about 28% of the time overall — not half.
- 5 and 6 are the dealer’s weakest cards (around 42% bust), closely followed by the 4.
- 7 through Ace are strong; the Ace busts least of all (under 12% with a blackjack peek).
- Against a weak up-card you stand, double and split more; against a strong one you build your own hand.
- Hitting soft 17 (H17) raises dealer busts slightly but still adds about 0.2% to the house edge.
Responsible gambling. Blackjack is a game of chance with a built-in house edge, and knowing dealer bust odds improves your decisions but cannot make the game profitable or predict any single hand. This page is informational only and is not betting advice. In Canada you must be of legal gambling age in your province or territory. If gambling is affecting you or someone you know, free, confidential help is available through the responsible gambling resources on this site, the Responsible Gambling Council, and provincial helplines such as ConnexOntario in Ontario.
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Frequently asked questions
How often does the blackjack dealer bust overall?
Averaged across every possible up-card, the dealer busts roughly 28% of the time in a standard game. The rate is much higher — about 40 to 43% — when the up-card is a 4, 5 or 6, and much lower — around 12 to 26% — when it is a 7 through Ace.
Which dealer up-card busts the most?
The 5 has the highest bust rate, at about 42.9%, with the 6 just behind at roughly 42.1%. The 4 is close too. These are the cards players most want to see, and they are why basic strategy turns conservative against a dealer 4, 5 or 6.
Why does the dealer’s Ace have such a low bust rate?
An Ace busts under 12% of the time in games where the dealer checks for blackjack first. The ace forms flexible soft hands that rarely bust on a single draw, and any ace that would have made a natural blackjack is already settled and removed before the figures are calculated.
Does it help me when the dealer hits soft 17?
Not on balance. Hitting soft 17 (H17) raises the dealer’s bust rate on a few up-cards, but it also lets the dealer turn weak 17s into stronger totals more often. The overall result adds about 0.2% to the house edge, so an S17 table is slightly better for players.
Can I use dealer bust odds to beat the game?
They help you make better decisions, but they do not overcome the house edge on their own. Dealer bust probabilities are already built into basic strategy, which trims the edge to around half a percent. The game still favours the house over the long run, so treat the odds as a tool for smarter play, not a winning system.
