Poker trackers are your friends

August 24, 2010  

By John Lanier

There are two poker camps: players who win by “feel” and those who “work it out.” I’m a firm believer math is the key to good poker. For most people math is a challenge.

When it comes to online poker we have an ally. The computer is the best math buddy you’re going to find. What am I talking about? Online poker trackers, a.k.a. player databases, which are legal on major poker sites.

Two of the most popular programs are Hold’em Manager, and Poker Tracker 3. These programs accumulate information about each hand you play, cash game or tournament, as well as information on opponents. The software displays historical information collected on the players in the database. While you play, a popup on your screen shows information you desire. This is called a HUD, or heads-up display. The HUDs are configurable and can be very powerful.

Two of the most common measurements are VPIP% (voluntarily puts in pot) and PFR% (preflop raise) percentages. These, obviously, indicate how aggressive the player is preflop. The key measurement is aggression in postflop play. Is your opponent aggressive, passive or neutral? A passive player will tend to check or call postflop. An aggressive player can be expected to make a continuation bet or raise after the flop. Another aggression factor is how often your opponent takes a hand to showdown. Let’s examine the aggression factor first.

AF = (raise percentage + bet percentage) / call percentage

The aggression factor is a measure of action after the flop, not before it. It’s calculated by dividing the percentage of times they bet or raise by the percentage of times they call. The aggressive player will be more than 1.5, and passive less than 1 on this scale. Opponents with a large AF typically bet or raise after the flop. Players with a passive AF typically check or call hands.

Went To Showdown Percentage (WSD%)

Just like it sounds, this is a measurement of the percentage of time your opponent stayed in the hand until the end. Most people know you only hit the flop one out of every three times. If your opponent’s WSD% is better than 33 percent then he’s overplaying his hands. If the percentage is smaller then they’re playing a very solid game employing a FIT-or-FOLD type of postflop strategy.

Went To Showdown and Won (WSDW%)

This is the number of times they won the pot after all of the cards are out. A high percentage is playing well postflop. A low percentage indicates a flush or draw chaser. They’re staying with a bad hand too long and showing down weak hands. An example of these weak hands would be top pair with a weak kicker or second pair.
Interpreting postflop information

Player Hands VPIP% PFR% AF WSD% WSDW%
Duke 50 44 22 2.1 12 83
Rusty 50 10 10 0.6 4 100
Chuck 50 35 30 2.5 24 6

Let’s see what we can learn from Duke. He has an AF of 2.1, indicating he bets or raises twice as much as he checks or calls after the flop. You can expect a continuation bet from this guy. He went to showdown only 12 percent of the time. He’s aggressive, but knows how to fold a hand on the turn. Expect Duke to challenge you on the flop and back off when you reraise him. Duke wins those hands that go to showdown 83 percent of the time. If Duke calls your reraise you should believe he probably has the better hand.

Here are Duke’s stats broken down:

• He was dealt 50 hands
• He voluntarily played 22 hands (50 * 44%)
• He raised 11 of those 22 hands. (50 * 22%)
• He bet or raised twice as many times as he called after the flop. (AF = 2.1)
• He went to showdown six times. (50 * 12%)
• He won at showdown five of six times. (50 * 83%)

So, how do you beat Duke? Wait till he raises postflop and reraise him with any two cards. About half the time (mathematically) he will not have a hand and will fold. If he plays back at you, believe he’s holding a monster hand and get away from yours.

From these stats and what you’ve learned, if Rusty is in a hand how should you react? If Chuck value bets you on a weak river card; what should you do? The math will keep you straight and hopefully build your bankroll.

WCOOP: PokerStars’ World Championship of Online Poker begins Sept. 5. Last year more than $50 million was awarded across 45 tournaments. This year there are 62 WCOOP events, with three running that first day: $215 no-limit hold’em six-max, a $215 two-day NLHE event and the $10,300 NLHE High Roller tournament at 3 p.m. ET. If you don’t have a PokerStars account and want to get started go to and click on the PokerStars link on the right-hand side of the home page.

— John Lanier plays as “WildHare” on most poker sites and lives in Lutz, Fla.