How to calculate the casino's edge in blackjack

I often get inquiries from casino players that want to know what the casino edge is for a specific blackjack game that they may have seen in a casino. In this article, I will show you how you can go about doing this on your own using several different tools.

One way to compute the casino's edge is to use data that is readily available in most blackjack books on how much a particular rule will increase or decease the player's overall expectation. For example the following data is in my book, Blackjack: Take The Money & Run, and it lists the effect each rule has on the casino's edge over the basic strategy player. I averaged the overall effects in the data below for each rule to give the player a rough idea on what the casino's edge is for a particular game (technically, the effects will differ slightly based on the number of decks of cards). A positive effect means the casino edge increases; a negative sign means it decreases the casino's edge (i.e., player favorable).

So how do you use the data? Easy. The effects are additive, so just sum them to get a quick and dirty idea on what the casino's edge is for a given set of rules.

For example, suppose your local casino is offering a 6-deck game where the dealer hits soft 17 and you can double down after pair splitting. Another casino might offer a 2-deck game where the dealer stands on soft 17, you can double after pair splitting and they also allow you to resplit aces. What is the approximate casino edge for these two games?

For the 6-deck game, if you add the effects listed in the table you would arrive at a casino's edge of +0.66% (6-deck game +0.59%, hit soft 17 +0.20%, DAS -0.13%). For the 2-deck game, you'll get +0.17% (2-deck game +0.35%, DAS -0.13%, RSA -0.05%). If you are a basic strategy player, you are better off at the 2-deck game where the casino's edge is about 0.5% lower.

If you have access to a computer, there are several web sites that have basic strategy calculators where you just input the rules and presto the computer instantly calculates the casino's edge. One easy-to-use blackjack house edge calculator can be found on www.wizardofodds.com in the blackjack section. It has limited rules, but it is very easy to use. You just click on the appropriate playing rules on the screen and you'll see the casino's edge at the bottom of the table.

For example, suppose you want to know what the casino's edge is for an 8-deck game where dealer stands on soft 17, you can double after pair splitting, late surrender is offered, you can resplit aces, and split up to 4 hands. By just clicking on the above rules on the calculator, you arrive instantly at a casino edge of +0.433%. Belterra casino in Indiana offers a single-deck game with the dealer standing on soft 17 and players can double after pair splitting. If you input these rules into the blackjack calculator, you arrive at a casino edge of -0.11% (i.e., the player has the edge over the casino, a great game).

Another site that has a blackjack house edge calculator is www.blackjackinfo.com. At this site you not only can obtain the casino edge for any set of rules but you can also obtain a color chart of the basic playing strategy (which you can print and take with you to the casino).

You'll find the most comprehensive house edge calculator for blackjack at www.trackjack.com. Their Trackjack Edge calculator handles all the standard rules plus odd payouts (like suited 6, 7, 8 paying 2 to 1), not so frequent rule variations (like 6-card 21 automatically wins) and even the European no-hole card rule (useful for calculating the house edge in blackjack games on Internet sites that have this rule). This site also maintains a continuously updated list of blackjack rules for every casino in US and Canada. You must be a subscriber to Blackjack Forum magazine in order to access the information on the site.

Another way to compute the house edge for any set of rules is to run a simulation on a blackjack software program. The one I recommend is Blackjack 6-7-8 by Stickysoft. The program will also do a lot more, like teach you the basic playing strategy (it will also generate color strategy charts that you can print), teach you how to card count (the program is an excellent tool for this), and even run a million hand simulation using a playing and betting strategy you choose (software will compute the win rates).

Use the above tools to figure out what the casino's edge is for any set of rules you might encounter. Remember, the keys to decreasing the casino's edge in blackjack are to first of all learn the basic playing strategy and then to play the games that have the most player favorable rules (i.e., where you calculate the lowest house edge using any tool presented in this article).