Texas Test’em

TexasTestemScreenshot1I created this simple Texas Hold’em odds calculator in 2008. It was my first iPhone project, and it was in the App Store on opening day. It is no longer available.

Just drop a few cards into place (leaving any unknown hands empty), and the program will immediately begin calculating the chances that each hand will win or tie by the river. You can view similar results for the turn or the flop. These Monte-Carlo calculations will be accurate to the first decimal place within a few seconds, and will become increasingly accurate as time passes.

You can also switch into Push Mode to perform “Sklansky-Chubukov” calculations. Set up a situation in which you’d consider pushing all-in, and the program will calculate what your opponents would do even if they could somehow see your hand. The resulting numbers represent a very conservative baseline that can help you decide whether or not to push all-in.

Either mode handles up to nine opponents in both pre-flop and post-flop situations.

If you have questions or comments about the program, feel free to contact me.

How To Use Texas Test’em

  • To change the number of players, swipe the poker table to the left or right.
  • To set up a situation that you want to test, drag cards from the lower panel into the cardholders on the poker table. Any cardholders that you leave empty will count as random cards during the program’s calculations.
  • To clear a situation that you’ve set up, shake the device. To undo a clear, shake the device again.
  • To toggle between Odds Mode and Push Mode, double-tap the poker table.
  • In Odds Mode, to see the odds of having the best hand by the turn rather than the river, tap the river cardholder to disable it. To test the odds of having the best hand by the flop, tap the turn cardholder to disable it.
  • To zoom in on any hand and see what the colored numbers mean, tap the panel above the hand.
  • To toggle between four-color cards and standard red/black cards, go to the Texas Test’em section of your iPhone’s Settings page.

How To Interpret the Results

Texas Test’em calculates odds by performing hundreds of random trials per second and tabulating the results. The longer you leave a situation set up, the more accurate the displayed results will be.

In Odds Mode, the program simply displays the chances that each hand will be winning or tying by the river (or by the turn or the flop if you’ve set it up that way). The green numbers represent the winning chances, and the yellow numbers represent the tying chances. Remember that empty cardholders represent random cards, so you can test how your hand would fare against a random hand by leaving an opponent’s cardholders empty.

TexasTestemScreenshot2In Push Mode, the program performs “Sklansky-Chubukov” calculations. In this mode, you’ll usually leave your opponent’s cardholders empty, to indicate that you’re pushing all-in against unknown hands. For each trial, the program will deal out random cards to all of the empty cardholders in all of the hands, and then decide which opponent (if any) should call your all-in. An opponent will only call with a hand that’s as good as or better than yours, and only the opponent with the best hand will call. If you do get called, the program will deal out the rest of the board and then determine who wins the hand.

Based on these calculations, the program displays four key results for each hand at the table. The green numbers represent the chances that each hand will go to showdown and win. The yellow numbers represent the chances that each hand will go to showdown and tie. The red numbers represent the chances that each opponent will fold a worse hand than yours. The cyan number in your own hand represents the chances that all of your opponents will fold. This number therefore represents the chances that your hand is currently the best one at the table.

The most important number is the purple one. This number represents multiples of the big-blind (if you’re pre-flop) or multiples of the total size of pot (if you’re post-flop). The program calculates your positive expected-value for the times when all of your opponents fold, and offsets it with your negative expected-value for the times when you get called by a better hand. The purple number represents the point at which these two numbers break even. If you have fewer than this many big-blinds in your stack (or fewer than this many times the pot if you’re post-flop), moving all-in almost certainly has a positive expected-value.

Notice that this calculation is extremely conservative. It estimates when it would be correct to push all-in even if your opponents could see your hand. In real-world situations, your opponents can’t see your hand, so they’ll sometimes fold hands that are better than yours, and sometimes call with hands that are much worse than yours. Therefore, it may well be profitable to push all-in in a given situation even if your stack is larger than the purple number. On the flip-side, if your stack is smaller than the purple number, pushing all-in isn’t necessarily the best play. If your hand is very strong, it might be even more profitable to limp in or make a small raise, to try to get more money out of your opponents.

Furthermore, there are times when it may be correct to fold even though your stack is smaller than the purple number. That’s because this calculation does not take tournament equity into account. If you’re on the bubble in a tournament, and one of the other players is about to go broke, it may be a bad idea to push all-in, even if your expected-value in chip equity is almost certainly positive.

Examples

Example #1: You’re playing an online sit-n-go. There are five players remaining, and the blinds are 50/100. You have 800 chips in your stack, and you’re on the button with the Queen of Spades and the Ten of Hearts. The first two players fold to you. What do you do?In Texas Test’em, switch into Push Mode and swipe the table left or right to set it to two opponents. Give yourself the Queen of Spades and Ten of Hearts, and leave the cards in your opponent’s hands empty. The program will indicate that your chances of having the best hand are just under 40%, and that pushing all-in is certainly profitable if you have fewer than 5.8 big-blinds. In fact, you have more than that in your stack, but remember that the Push Mode calculations are very conservative. It would be profitable to push all-in with queen-ten here even if your opponents could see your hand. In a real situation, one of your opponents might fold a hand like king-deuce, which is better than your queen-ten, or call with a hand like jack-ten suited, which you have crushed. (You can use Showdown Mode to determine how your hand fares against various hands that your opponents might call with.) You don’t have much more than 5.8 big-blinds left, so pushing all-in here is probably correct. If you were on the bubble, you might think about folding, as long as there was at least one other short-stacked player who might go broke soon.

Example #2: You’re playing an online sit-n-go. There are six players remaining, and the blinds are 50/100. You’re in the big-blind with a terrible hand—seven-deuce offsuit—and after posting the blind you have 800 chips left in your stack. Two loose players limp in middle position, and the small-blind folds. You feel that if you push all-in now, one of the limpers will almost certainly call you with a better hand, so you check. The flop comes 9-7-3 rainbow, giving you a pair of sevens. The pot contains 350 chips, and you’re first to act. What do you do?

In Texas Test’em, switch into Push Mode and swipe the table left or right to set it to two opponents. Set up your hand cards and the three board cards, while leaving your opponent’s hands empty. The program indicates that you have a 57% chance of having the best hand, and that pushing all-in against two random hands is certainly profitable if you have fewer than 2.4 times the pot-size in your stack. You have 2.28 times the pot size in your stack, so you should push all-in. Alternatively, you can go for a check-raise if you’re pretty sure that one of the other two players will bet after you check. However, your hand will lose some value if both opponents check behind you. (You can test different turn cards to see how the numbers change. Sevens and deuces are great for you, and nines are fine. All other cards give your opponents more ways to beat you.)

This example is more complex than the previous example. Since your opponents chose to limp, their hands cannot be considered completely random. But it’s still useful to perform calculations as if the hands were random, and use those results as a baseline. In actual fact, your hand on the flop fares well against the kinds of hands that players might limp in with (i.e. weak aces, low pocket pairs, random high-cards). Try putting an ace into one of your opponents cardholders—which is equivalent to pretending that at least one of your opponents holds at least one ace—and you will see that your numbers improve. As usual, the baseline provided by Push Mode is very conservative.

As you can tell from these examples, Texas Test’em doesn’t make decisions for you. Instead, it helps you hone your poker intuition so that you can make better decisions.

Have fun at the tables!