Trading Expectancy Calculator

What is trading expectancy?

Trading expectancy is a formula that measures whether a trading strategy has a positive or negative edge. It calculates the average profit or loss you can expect per trade over a large sample, based on the strategy's win rate, average win, and average loss.

In plain terms, expectancy answers one question. If you take the same trade setup many times, does it make or lose money on average?

A positive expectancy means the strategy has a statistical edge over time when it is executed consistently. It does not mean every trade is profitable or that losses can be avoided. Even profitable strategies go through losing streaks, drawdowns, and periods where results fall below expectations.

A negative expectancy means the strategy loses money over time because the average losses outweigh the average wins.

The difference between a strategy with a real trading edge and one that only appears profitable is whether the results hold up over a meaningful sample of trades. For a deeper look at how an edge shows up over a sample, read our guide to trading expectancy.

How is trading expectancy calculated?

The formula uses four inputs.

• Win rate is the percentage of trades that close with a profit.
• Loss rate is the percentage of trades that close with a loss.
• Average win is the average profit from your winning trades.
• Average loss is the average loss from your losing trades.

Your win rate and loss rate always add up to one hundred percent. For example, a strategy with a 60% win rate has 60% winning trades and 40% losing trades. The formula combines how often each outcome happens with the size of that outcome, then compares the expected gain from the winners against the expected loss from the losers.

A worked example

Assume a strategy wins 55% of its trades, with an average winning trade of $500 and an average losing trade of $250. The expected value from the winners is 55% of $500, which is $275. The expected value from the losers is 45% of $250, which is $112.50.

Subtract the losing side from the winning side and the expectancy is +$162.50 per trade, before fees, commissions, and execution costs. Over 100 trades that is roughly $16,250 in expected profit.

This does not mean you make exactly $16,250. Actual results vary because trades do not occur in a fixed order. Losing streaks, winning streaks, and market conditions all shape the actual equity curve. Those are the default numbers in the calculator above, so the equity curve you see is the path this math tends to produce.

What does R mean in trading expectancy?

Expectancy is often measured in R instead of dollars. R is the amount you risk per trade, so measuring in R lets you compare performance across different account sizes because the measurement stays consistent.

Say you risk $100 per trade. Then 1R is $100 of risk, a +2R winner makes $200, and a -1R loser costs $100. An expectancy of +0.5R is $50 of expected profit per trade. Over a large number of trades, +0.5R means the average outcome equals half of the amount you risk per trade.

What is a good expectancy in trading?

A solid trading system generally produces around +0.3R to +0.5R per trade after fees and trading costs. If you risk $100 per trade, that is roughly $30 to $50 of expected profit per trade. This level leaves enough room to handle normal drawdowns, execution mistakes, and small changes in market conditions.

Stronger systems may reach +0.5R to +1R per trade, but the acceptable level depends on several things.

• Strategy type
• Trading frequency
• Maximum drawdown
• Market conditions
• Execution consistency

A small positive expectancy is not always enough. A strategy at +0.05R can be profitable on paper, yet the edge is often too thin to survive real-world conditions.

• Spread and commissions
• Slippage
• Execution mistakes
• Changing market conditions
• Emotional decision making

The goal is not simply finding a positive number. The goal is finding an edge strong enough to survive real trading conditions and execute consistently.

How to use this calculator

• Enter your win rate. Divide your winning trades by your total trades and multiply by 100. For example, 55 winning trades out of 100 is a 55% win rate.
• Enter your average win and average loss. Use your real trading history where you can. Average win is total profit from your winners divided by the number of winners. Average loss is total loss from your losers divided by the number of losers.
• Read your expectancy result. The number is your expected average profit or loss per trade. A positive number means an edge, a negative number means the strategy loses over time, and zero means it is break-even before costs.
• Simulate different outcomes. Change the trade count and click Resimulate to see other possible equity curves. Each run keeps the same win rate, average win, average loss, and expectancy, and only the order of the wins and losses changes. That shows how the same strategy can take very different paths because sequencing affects short-term results.

How to read your result

Positive expectancy

A positive expectancy strategy has a statistical advantage. Short-term results can still swing widely because trades occur in random sequences, so a profitable strategy can sit through a losing streak or drawdown before it produces its expected results.

Negative expectancy

A negative expectancy strategy loses money over a large number of trades. Adding more trades does not improve the edge. It usually makes the negative results appear faster.

Break-even expectancy

A break-even strategy has an expectancy of zero, where the average gains and losses cancel out before costs. Once commissions, spreads, and execution costs come in, a break-even strategy turns negative.

Why the equity curve looks different each time

The equity curve is a simulation of the same trading statistics playing out in a different sequence on each run. The win rate, average win, average loss, and expectancy stay the same, but the order of the wins and losses changes.

One run may open with several losses before recovering. Another may begin with a strong winning streak and then fall into a drawdown. Click Resimulate to visualize the range of paths your stats can produce. This is why traders evaluate systems with expectancy, risk management, and sample size rather than judging performance from a short stretch of results.

Common mistakes when evaluating expectancy

Confusing win rate with profitability

A high win rate does not automatically mean a profitable strategy. A strategy can win 70% of trades and still lose money if the average loser is much larger than the average winner. Profitability comes from the relationship between probability and payoff, not the win rate alone.

Ignoring the reward to risk ratio

Expectancy depends on both how often you win and how much you make or lose on each outcome. A strategy that wins 40% of trades can still be profitable if the average winner is much larger than the average loser. The risk to reward ratio calculator shows how different combinations of win rate and reward to risk affect profitability.

Using too small a sample size

A small number of trades can create misleading results. A strategy may look profitable after a short period because of favorable conditions or simple luck. A sample of 20 trades or fewer is usually too small, because a few large winners or losers can dominate the result. A sample of a hundred or more is a better benchmark because the results become steadier and give a clearer view of whether the edge is real. Lower-frequency strategies may need more data because they produce fewer trades and need testing across different market conditions.

Frequently asked questions

What is positive expectancy in trading?

Positive expectancy means a strategy has an expected profit over a large sample of trades. It happens when the average value of the winning trades is greater than the average value of the losing trades once probability is accounted for. It does not guarantee short-term profits, and it still needs risk management, position sizing, and consistent execution.

What does the equity curve show?

The equity curve shows how an account balance changes as a series of trades plays out, using your win rate, average win, average loss, and number of trades. A rising curve represents positive expectancy over the simulated period. The dips are drawdowns, the declines you must be prepared to sit through. A profitable strategy does not produce a perfectly smooth curve, and periods of losses are normal even when the long-term edge is positive.

How do I visualize my expectancy over time?

Enter your win rate, average win, and average loss, then read the equity curve. The expectancy number shows the average outcome per trade, while the curve shows how that edge develops through different sequences of wins and losses. It helps you see the potential growth, the losing streaks, the drawdowns, and how much the results can vary.

Is this a Monte Carlo simulation of my trades?

It works like a basic Monte Carlo simulation. Each trade is generated at random as a win or a loss based on the win rate you enter, then added to the balance. When you resimulate, the same statistics are used but the order of outcomes changes, which creates different possible paths. A full Monte Carlo analysis can include more variables, but the core idea is the same, testing how a strategy behaves under different sequences of outcomes.

How many trades are needed to calculate expectancy?

A sample of a hundred or more is a good benchmark. A smaller sample, such as 20 trades or fewer, is usually not enough because a few unusually good or bad trades can dominate the result. A strategy can look highly profitable after 20 trades simply because conditions happened to favor it. With a hundred or more, the results become steadier and show whether the edge is real rather than short-term luck. Lower-frequency strategies may need more data to capture different market conditions.

Can a high win rate strategy have negative expectancy?

Yes. A high win rate does not guarantee profit. A strategy that wins 80% of trades but loses five times more on its losers than it gains on its winners can still have a negative expectancy. The size of the wins and losses matters as much as the percentage of winners.

Is expectancy the only thing that matters in trading?

No. Expectancy is one part of evaluating a system. A full read also considers maximum drawdown, risk per trade, position sizing, sample size, market conditions, and execution consistency. A strategy needs both a positive edge and sound risk management to survive, because a strong expectancy with poor risk management can still lead to heavy drawdowns or account failure.

What do profitable trading statistics look like?

There is no single perfect combination of win rate and reward to risk ratio, and different profitable strategies have different profiles. A higher win rate with smaller average winners wins more often but captures smaller moves. A lower win rate with larger average winners loses more often but makes up for it on the winners. A balanced win rate with a consistent reward to risk combines a reasonable hit rate with controlled risk. What matters is that the combination produces positive expectancy, keeps drawdown manageable, and can be executed consistently.