If you have analyzed your games with Extreme Gammon or XG and GNU Backgammon, you have probably seen numbers such as +0.35, -0.72, or +1.20 next to moves many times. But what exactly do these numbers represent? The answer can be summed up in one word: Equity.
Equity is one of the most fundamental concepts in modern backgammon. This number does not simply tell you what percentage chance you have of winning. Instead, it attempts to show the true value of a position. A simple win, gammon, backgammon, and, in Cubeful analysis, even the status of the doubling cube all affect it.
USBGF defines Equity in its backgammon glossary as the value of a player in the current game, which is mathematically equal to Expected Value. Put more simply, Equity answers this question: “If we play this exact position many times, on average, how much is this position worth to me?”
What Does Equity Mean in Backgammon?
Let’s start with a very simple example. Suppose we play a position 100 times under exactly the same conditions and get the following results:
You win 75 times
You lose 25 times
No gammons or backgammons occur
There is no doubling cube in the game
Each simple win is worth +1 and each simple loss is worth -1.
So:
(1×0.75) - (1×0.25) = 0.50
The Equity of this position is +0.50. This means that if you play this position a very large number of times, you will be ahead by an average of half a unit per game. GNU Backgammon also defines Money Equity as the expected monetary or scoring value of a position in a Money Game. For example, an Equity of +0.40 in a game with a one-dollar stake means that, in the long run, we expect to gain an average of 40 cents each time we encounter such a situation.
An Important Point
Win Rate and Equity are not the same thing. Win percentage only answers the question: “What percentage of games do I win?” But Equity asks: “How much are the total value of my wins and losses worth?” This small difference forms a large part of the logic behind professional backgammon analysis.
Why Does Equity Provide More Information Than Win Percentage?
Suppose you have two different moves. With the first move, you win 60 percent of the games, but almost all of those wins are singles. With the second move, you win only 56 percent of the games, but a significant number of those wins are gammons. Which move is better? Win% alone does not provide a clear answer. The second move may have higher Equity despite having a lower win percentage because some of its wins are worth twice as much.
For example, suppose:
Move A
Simple win: 60%
Simple loss: 40%
Simple Equity:
(1×0.60) - (1×0.40) = 0.20
But for Move B:
Simple win: 45%
Gammon win: 12%
Simple loss: 43%
Equity:
(1×0.45) + (2×0.12) - (1×0.43) = 0.26
Although the overall chance of winning with Move B is only 57 percent, its expected value is higher than Move A. This is where things get interesting: the highest Win% does not always mean the best move.
What Do Positive and Negative Equity Mean?
In the simplest model, without a doubling cube:
Certain simple win = +1
Completely equal position = 0
Certain simple loss = -1
But gammons and backgammons expand the range of these numbers.
For the player being analyzed:
Simple win = +1
Gammon win = +2
Backgammon win = +3
Simple loss = -1
Gammon loss = -2
Backgammon loss = -3
So, for example, +0.40 does not mean that you win exactly 70 percent of your games. Different combinations of Win, Gammon, and Backgammon results can produce the same Equity. This is one reason why you should not directly convert an Equity number into a win percentage.
What Is the Simple Equity Formula?
GNU Backgammon provides a formula for Cubeless Money Equity that takes into account the probabilities of winning, gammons, and backgammons for both players. In simple terms, the logic of the formula is:
Value of your wins - value of your losses
For example, suppose the outcome of a position is:
50% simple wins
10% gammon wins
40% simple losses
Then:
(1×0.50) + (2×0.10) - (1×0.40) = 0.30
So from your perspective, this position has an Equity of approximately +0.30. In other words, continuing the game from this point has positive long-term value for you. This model is still a simplification. When the doubling cube and the possibility of Double and Redouble enter the game, calculating Cubeful Equity becomes more complicated.
What Is Cubeless Equity?
Cubeless Equity means evaluating the value of a position without considering the future effect of the doubling cube. Imagine that the cube does not exist at all. The game continues until the end and the result is one of these:
Simple win
Gammon
Backgammon
Simple loss
Gammon loss
Backgammon loss
The probability of each outcome is determined, and then the total expected value of the position is calculated. This is what GNU Backgammon calls Cubeless Money Equity. Cubeless Equity is very useful for understanding the raw quality of a position, but it does not tell the whole story because, in a real game, the doubling cube itself is an asset.
What Is Cubeful Equity?
With Cubeful Equity, the doubling cube becomes part of the calculation. Now the software does not only ask, “What happens if the game continues to the end?”
It also considers questions such as:
Is now a good time to Double?
If we Double, will the opponent Take or Pass?
Who currently owns the Cube?
Will there be an opportunity to Redouble in the future?
How much is it worth to hold the Cube?
If the position changes, how much will the Cube Equity increase or decrease?
GNU Backgammon explicitly explains that calculating Cubeful Equity is much more complicated than Cubeless Equity and that the future value of the cube must also be incorporated into the model to estimate it. This is why two positions with the same win percentage can have different Cubeful Equity.
An Example of the Value of the Doubling Cube
Suppose in a simple Money Game:
You have an 80% chance of winning
You have a 20% chance of losing
We temporarily ignore gammons and backgammons
Cubeless Equity is:
(1×0.80) - (1×0.20) = 0.60
But now suppose you have a position where a Double is unacceptable to your opponent and they Pass the Cube. In a game with a current stake of one unit, if your opponent Passes, you immediately win that one unit. The immediate Equity in this situation is +1.
Interesting, right? Your Win% is still 80 percent, but the right to use the Cube changes the value of the position. Of course, this is only an educational example. In a real position, the probabilities of Take, Pass, Redouble, Gammon, and future changes in the position must also be considered.
Which Is More Important, Cubeful or Cubeless?
The answer depends on the question you are asking about the position. If you want to know how strong the position of the checkers itself is, Cubeless Equity provides a simpler picture. But if you are making a decision about Double, Take, or Pass, Cubeful Equity is much more important.
In a real game, the Cube is not merely a tool for increasing the score. Cube ownership itself has value. A player who owns the Cube may have the right to Redouble in the future, and that option forms part of the Equity of the position.
What Is the Difference Between Equity and MWC?
This is where one of the common mistakes occurs when players begin working with XG and GNU. In Match Play, there is another important concept: MWC = Match Winning Chance, meaning: the probability of winning the entire Match from the current position. USBGF also defines Match Equity as the chance of winning the match based on the current Score. Suppose we have a race to 7 points.
Compare these two situations:
Score 0-0
Score 6-5
The value of winning one point is not the same at these two Scores. At 6-5, the player with 6 points finishes the entire Match with a simple win. Therefore, the value of different game outcomes must be evaluated based on their effect on the probability of winning the match. For this reason, GNU Backgammon uses Match Winning Chance in Match Play and calculates it with the help of a Match Equity Table.
So, simply:
Money Game → Money Equity is the primary metric
Match Play → MWC and Match Equity are the primary metrics
What Is Match Equity?
Match Equity is the probability of winning the entire match from a specific Score. For example, 50 percent Match Equity means that, assuming equal player strength and specified match conditions, each side will win approximately half of the matches from that position. This number does not depend only on the position on the board. The Score also matters.
For example, a position that has an obvious Double in a Money Game may not be a Double at all at a particular Match Score. Why? Because the goal in Match Play is not to maximize the number of raw points. The goal is to maximize the probability of winning the entire match. This difference is one of the most important steps toward entering professional match backgammon.
Why Is the Best Move Not Always the Move With the Highest Win%?
Suppose XG recommends two moves:
Move
Win%
Equity
Move A
54%
+0.18
Move B
52%
+0.31
If you look only at the Win% column, A appears better. But the software chooses Move B. Why?
B may:
Win more gammons
Reduce the probability of losing a gammon
Create a better position for the Cube
Create a stronger board
Put more pressure on the opponent's checker structure
As a result, despite having a lower Win%, it has higher expected value. This is exactly the change that learning Equity creates in a player's way of thinking. Instead of asking only, “Which move wins more often?”, you ask: “Which move produces more value overall?”
What Is Equity Difference?
When analyzing XG or GNU, you will usually see several moves with different Equity values.
For example:
Best Move: +0.350
The move you played:
Played Move: +0.180
Difference:
(0.350) - (0.180) = 0.170
This means your choice lost approximately 0.17 Equity units compared with the best move.
This number is much more important than the move's rank.
Suppose the best move has an Equity of +0.420 and the second move has +0.418.
The difference is only:
0.002
In practical terms, the two moves are extremely close. So the fact that the software labels a move “#2” does not by itself mean that you made a major mistake. Equity difference is what shows the size of the error.
Does Negative Equity Always Mean the Position Is Bad?
Not necessarily in the way a beginner might think. Negative Equity means that, in terms of expected value, the situation favors the opponent.
For example:
-0.15
means the opponent has an advantage, but this number is worlds apart from -0.90. The former may be a completely playable position that still has plenty of chances. The latter indicates that the expected value of the position is significantly against you. So it is better to think of Equity as a spectrum rather than a simple “good” or “bad” label.
How Is Equity Related to a Double Decision?
One of the most important places where Equity comes into play is Cube Action. Suppose your opponent offers you a Double. You have two main choices: Take or Pass. With a Pass, the game ends immediately and you lose the current value of the game. With a Take, the game value doubles and you continue playing. To make the correct decision, you need to compare the Equity of the two options. If the Equity of accepting the Cube is better than Passing, Take has greater value. If Pass produces a smaller loss, you should reject the Cube. This is where concepts such as Take Point, Cash Point, and Double Point come into play.
What Does a Take Point of Around 25 Percent Mean?
In the simplest Money Game model, without Gammons and with a live Cube, the Take Point is usually explained as being close to 25 percent. But this number is not a fixed rule for every position.
The following factors can change the Take Point:
Gammon
Backgammon
Cube Ownership
Recube Potential
Match Score
Crawford and Post-Crawford
Dead Cube or Live Cube
So the statement, “I have a 30 percent chance of winning, so I should definitely Take,” is incomplete. A better question is: 30 percent chance of winning with what amount of gammon losses, what Cube status, and at what Match Score? This is exactly where the difference between superficial and professional analysis becomes clear.
How Does Gammon Equity Affect Decisions?
Suppose two moves have almost the same Win%. The first move creates a calm position in which most of its wins are Singles. The second move enters a Blitz and increases the probability of a gammon. In a Money Game, the second move may produce higher Equity even if it carries more risk. Conversely, sometimes you do not need a gammon from a match perspective. In such situations, the safer move may have greater value.
So saying “an aggressive game is better” or “a safe move is better” does not mean much by itself. The real question is always: How does this choice change Equity?
Why Is Equity Important in Software Analysis?
Suppose that after a match you find 15 mistakes in XG. Not all of these errors have the same value. One move may lose only 0.010 Equity while another loses 0.300. Clearly, if you want to improve, examining the second error is more important. Instead of simply counting Errors and Blunders, examine:
Where did the largest Equity Loss occur?
Was the error in Checker Play or a Cube Decision?
Did you misjudge the Gammon Value?
Was it a wrong Take/Pass decision?
Did you misunderstand the Timing or Structure of the position?
This method will get you to the real patterns behind your mistakes much faster.
Do We Need to Memorize the Equity Formula?
No. You are not supposed to pull out a calculator in the middle of a match and calculate Expected Value! The main purpose of learning Equity is not memorizing the formula. It is training your mind to understand the value of different outcomes. When you analyze hundreds or thousands of positions with XG, you gradually begin to understand:
Why some 55-percent positions are more valuable than 60-percent positions
Why Gammon Chance is sometimes decisive
Why Cube Ownership has value
Why a move can lower Win% while increasing Equity
Why the same position can lead to a different Match decision at a different Score
This understanding is much more important than memorizing a few formulas.
Equity Shows the Outcome of a Decision, Not the Reason Behind It
This may be the most important part of the entire article. Suppose XG says Move A = +0.420 and Move B = +0.310. Now we know that A is better. But we still do not know something more important:
Why? Does A hit an opponent's checker? Does it build a better Prime? Does it preserve Timing? Does it provide better Diversification? Does it increase Gammon Chance? Does it reduce the probability of a gammon loss? Does it create a better Cube Position? The software gives you the result of the calculation. The player must find the logic behind it. This is where using XG goes beyond “checking the correct answer” and truly becomes backgammon training.
A Better Way to Analyze Equity in XG
When XG shows the best move, do not immediately jump to the top-ranked move. First, look at the Position again and try to guess why that move should be better.
Then compare these factors:
Win%
Gammon Win%
Gammon Loss%
Equity
Equity Difference
For example, you may discover that the best move has 2 percent less Win%, but wins 8 percent more gammons. Suddenly the Equity number makes sense. This type of analysis is much more educational than simply memorizing the move suggested by the Bot.
A Final Example
Suppose you have two moves:
Move A
Win: 60%
Gammon Win: Low
Gammon Loss: Low
Equity: +0.22
Move B
Win: 57%
Gammon Win: Much higher
Gammon Loss: Slightly higher
Equity: +0.34
A player who only looks at Win% will prefer A. A player who understands Equity will ask: “Why does B have greater value despite winning less often?” The answer is probably found in Gammon Value, position structure, or Cube Potential. This is the question that takes you from memorizing moves to understanding backgammon.
Final Thoughts: Equity Is the Number Behind Decisions
If we had to summarize the entire article in one sentence: Equity is the expected value of a position, a number that combines wins, losses, gammons, backgammons, and, in Cubeful analysis, the effect of the doubling cube into a common metric. So the next time XG shows +0.25 or -0.40, do not just focus on whether it is positive or negative.
Ask yourself: “What makes this position worth +0.25?” The answer may lie in the win percentage. It may be Gammon Chance. It may be Cube Ownership, or perhaps a move that completely changes the future structure of the game.
Once you start asking “Why did Equity change?”, computer analysis no longer gives you only the right or wrong answer. It becomes a tool for understanding the real logic of the game. And perhaps this is the most important step in modern backgammon: move away from result-oriented thinking and play with a decision-oriented mindset.