Gambling Tips > Blackjack


By Henry Tamburin

That’s the mantra of blackjack players everywhere when the dealer begins to flip over her draw card. At this split second, players are hoping (some are even getting a little religion and praying) that the card will bust her.  


Sometimes when you play blackjack, the dealer will obligingly bust hand after hand. Other times, she will deal an entire shoe and never bust. It would be nice if we had some idea before we played our hand of the chance that the dealer will bust. It turns out that the key to knowing whether the dealer is going to bust or not is staring right at you on every hand. Stay with me and I’ll explain.


So, let’s look at the big picture first, and let me ask you this: How many times, say in every seven hands, do you think that the dealer will bust? Once? Twice? Maybe four times? The answer is twice. Yep, on average the dealer is going to bust about two times in every seven hands (which equates to 29 percent, rounded). That’s an interesting statistic but it doesn’t really help us when we are staring at a dealer 7, holding a 10-6, and deciding how to play the hand.


Fortunately for blackjack players, there happens to be a correlation between ... are you ready for this ... the dealer’s upcard and the percent of the time she will bust (no kidding). The mathematicians have done all the calculations and ... drum roll please ... here are the data.


Dealer’s Upcard











Chance of Busting











Note: The above percentages are for a six-deck game, dealer stands on soft 17, and assumes that the dealer has checked that she doesn’t have a blackjack. Source: Play Blackjack Like the Pros by Kevin Blackwood.

If you take a second and glance from left to right at the dealer’s bust percentages in the table, what strikes you? Do you see the significant drop between a dealer’s 6 and 7 upcard? The numbers clearly show that the dealer’s chance of busting is greater when she has a small upcard (2 though 6), and less when her upcard is a big card (7 through Ace).


The reason the dealer busts more often when she has a small upcard is because her initial two-card hand will be less than 17, and by the house rules, she must hit (with one exception: if she happens to have an Ace-6 and the rules specify that she stands on soft 17). As long as the dealer has to hit in order to get to 17–21, there is a good chance that she will bust.


On the other hand, when the dealer shows a 7 through Ace upcard, her chance of having an initial
two-card pat hand of 17–21 is much better (all she needs is a ten-value card in the hole—and there are 16 of them per deck when you include the Js, Qs, and Ks—or an Ace) and, therefore, she will bust less often.


It is, therefore, no accident that the basic blackjack playing strategy diverges below and above dealer’s upcard of 6 and 7. You generally will stand when you have a stiff hand (12 through 16), and the dealer shows a small upcard because, according to the above percentages, the dealer’s chance of busting is relatively high (remember that if you bust and the dealer subsequently busts, you automatically lose which is why it’s better to stand on most stiff hands when she shows a small upcard). Likewise, we tend to double and split more often when the dealer shows a small upcard partly because her chance of busting increases. On the other hand, when the dealer shows a 7 through Ace and has less chance of busting and a greater chance of making a pat 17–21, you shouldn’t be standing on stiff hands. In fact, risky as it sounds, the best play to make is to hit your stiff hand until you achieve a total of 17–21 (or bust out trying). Make sense? (If so, you should now know how to play the 10-6 against a dealer’s 7 upcard ... with a stiff hand against a dealer’s 7, the correct play is to hit.)


In today’s world, more casinos are implementing the h17 rule, meaning their dealers no longer stand on soft 17 (s17) and hit instead. When the rules specify h17, the dealer’s chance of busting when she has a 6 and Ace upcard increases (with a 6, it increases from 42 to nearly 44 percent, and with the Ace, from 17 to 20 percent). Because the dealer busts more often, this would appear to make an h17 game better for players than an s17 game. However, here’s the rest of the story. When the dealer hits her soft 17 hand and doesn’t bust, she will now improve her soft 17 and achieve a final hand of 18 through 21 more often than with s17, and that is not good news for players. In fact, the latter more than compensates for the increase in the dealer’s bust percentage, resulting in a net increase in the house edge against players of about 0.2 percent when casinos implement the h17 rule.

Now that you have some idea on the chance that the dealer will bust by just looking at her upcard, you will better understand why the basic playing strategy tells you to hit some hands and stand on others. And this will help you become a better blackjack player.