If you are playing a shoe game with eight decks and can double on anything, the basic house edge is -0.55% a little more than half of one percent. Other rules relating to doubling and either reduce or increase this basic house edge.
Double after splitting reduces the house edge by .13 % to -0.42
Double on 10 and 11 only - .21 increase the house edge to -0.76
By using basic strategy you can determine when you should double down based on the mathematics of the game The reason that doubling down is so favorable is that you are doubling your bet when you have the best opportunity of beating the dealer. Most of the time, this is when the dealer is at their weakest. This happens when the dealer shows an up card, which can possibly cause them to bust.
Many computer simulations have been run to determine the frequency that a dealer will bust based on their up card. Take a look at the table at the bottom of this page.
The worst cards for the dealer are the two through six. They will bust more times with these cards showing. Your double down will be successful more against these cards. There are other situations where you will double down with a ten against the dealer's nine or an eleven against a dealer's ten. These are close calls and some newer players hesitate to do this. Although you will not be as successful with these plays as many times as when the dealer has a smaller card it is still the correct strategy to do so. In the long run you will win more money by doubling in these situations than you will lose.
Go For It
Some players are hesitant to double down because they are afraid of losing a double bet. If the size of your bet when you double down makes you sweat, then you are playing at table stakes higher than you should be.
Most casinos will let you double down for less than your original bet providing it meets the table minimum. This is foolish. You only double in favorable situations and it are to your advantage to double for the maximum. Strike while the iron is hot!!
As an experienced player I can say that I love double down situations. But you must realize that there will be times when you will run into a negative streak. I have had some nights when the majority of my double down hands were losers. Its frustrating but negative fluctuations occur. If you are a newer player and this happens, you may have a tendency to want to deviate from correct strategy and not double down. Do not give in to the temptation.
Doubling down is extremely profitable and it is factored in to the figures that are computed for the house edge. When you dont double down in the proper situations you are not playing correct basic strategy and you will be increasing the house edge. Seize the moment and double down when you can.
Delaer Bust Percentage
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