TRADING
Trading Expectancy Calculator — Does Your Strategy Have an Edge?
By Worldtickers ·
Use our free trading expectancy calculator to determine whether your strategy has a positive edge. Enter your win rate, average winning trade, and average losing trade to find your expected profit per trade in dollars.
This trading expectancy calculator — does your strategy have an edge? tool focuses on use our free trading expectancy calculator to determine whether your strategy has a positive edge. Enter your win rate, average winning trade, and average losing trade to find your expected profit per trade in dollars. Use it to size trades, compare risk levels, estimate market exposure, and review entries, exits, volatility, leverage, and stop levels before committing capital.
Trading Expectancy Calculator
Expectancy Calculator
Calculate the expected profit or loss per trade based on your win rate and average win/loss sizes.
What Is Trading Expectancy?
Trading expectancy is the single most important metric for evaluating whether a trading strategy has a mathematical edge. It answers a deceptively simple question: on average, how much money does each trade make or lose? A strategy with a positive expectancy of $30 per trade will, over a large enough sample, make approximately $30 for every trade taken — regardless of which specific trades were winners and which were losers. A negative expectancy means you are losing money on average, and no amount of clever trade selection can overcome a strategy that is structurally unprofitable.
What makes expectancy so valuable is that it combines the two dimensions of trading performance — win rate and win/loss size — into a single dollar figure. A high win rate is meaningless if your losses are much larger than your wins, and a high reward-to-risk ratio is meaningless if your losses are so frequent that they overwhelm the occasional large win. Expectancy captures the interaction of both dimensions, giving you a true picture of whether your strategy makes money on a per-trade basis.
The concept is borrowed from probability theory and gambling mathematics. In a casino, the house has a positive expectancy on every bet — the odds are structured so that the casino makes a small amount on each bet, and over thousands of bets, that small edge compounds into guaranteed profit. A trader with a positive expectancy is in the same position relative to the market: each trade makes a small amount, and over hundreds or thousands of trades, that small edge compounds into significant returns. The key difference is that a trader must identify and maintain the edge themselves, while the casino's edge is built into the rules of each game.
Expectancy is not a prediction of what any individual trade will do — it is a statistical average that only becomes meaningful over a large sample. In any single trade, the outcome is random relative to the expectancy. But over hundreds of trades, the average outcome converges toward the expectancy, just as the average result of flipping a fair coin converges toward 50% heads as the number of flips increases. This is why expectancy is a long-term metric, and why short-term results can deviate wildly from the calculated expectancy without invalidating it.
How to Use This Calculator
This trading expectancy calculator takes three inputs — your win rate, your average winning trade size, and your average losing trade size — and outputs your expected profit or loss per trade in dollars.
Win Rate (%)
Enter the percentage of your trades that are winners. If you have a track record, use your actual historical win rate. If you are evaluating a new strategy, use conservative estimates based on backtesting or paper trading. Win rate should be calculated over at least 50 to 100 trades for a meaningful estimate. A win rate calculated over fewer trades is too noisy to be reliable.
Average Winning Trade ($)
Enter the average dollar amount you make on winning trades. If your last 50 winning trades generated a combined profit of $15,000, your average winning trade is $300. Include only the trade profit, not the position size — the calculator needs to know how much you win per trade, not how much you traded.
Average Losing Trade ($)
Enter the average dollar amount you lose on losing trades. Use a positive number — the calculator treats it as a loss. If your last 50 losing trades lost a combined $12,000, your average losing trade is $240. This number includes your stop-loss losses, slippage, and any other costs specific to losing trades.
The Formula Explained
The expectancy formula is: Expectancy = (Win Rate × Average Win) − (Loss Rate × Average Loss).
Where Win Rate is the probability of a winning trade (expressed as a decimal, e.g., 0.55 for 55%), Loss Rate is 1 − Win Rate, Average Win is the average dollar gain on winning trades, and Average Loss is the average dollar loss on losing trades. The formula multiplies each outcome by its probability and subtracts the expected loss from the expected gain.
Using the example from earlier: a 55% win rate with an average win of $300 and an average loss of $240 produces an expectancy of (0.55 × $300) − (0.45 × $240) = $165 − $108 = $57 per trade. This means that, on average, each trade is worth $57 to you. Over 100 trades, you would expect to make approximately $5,700 — before accounting for commissions and other costs.
If you want to include commissions, subtract them from the expectancy. If your round-trip commission is $10 per trade, the net expectancy becomes $57 − $10 = $47 per trade. Always calculate expectancy net of all costs for the most accurate assessment of your strategy's true edge.
Real-World Examples
Example 1: A Scalping Strategy
A day trader scalps index futures with a 62% win rate. Average winning trades make $80, and average losing trades lose $65. Expectancy: (0.62 × $80) − (0.38 × $65) = $49.60 − $24.70 = $24.90 per trade. After accounting for $5 in commissions per round trip, the net expectancy is $19.90 per trade. At 20 trades per day, this strategy generates approximately $398 per day in expected profit — roughly $8,360 per month over 21 trading days.
Example 2: A Trend Following Strategy
A swing trader follows trends with a 40% win rate but a 2.8 reward-to-risk ratio. Average winning trades make $700, and average losing trades lose $250. Expectancy: (0.40 × $700) − (0.60 × $250) = $280 − $150 = $130 per trade. Despite losing 60% of trades, this strategy makes $130 per trade because the winners are almost three times larger than the losses. This demonstrates why win rate alone is a misleading metric — the ratio of wins to losses matters just as much.
Example 3: A Losing Strategy
A trader has a 48% win rate, average wins of $200, and average losses of $220. Expectancy: (0.48 × $200) − (0.52 × $220) = $96 − $114.40 = −$18.40 per trade. This strategy loses $18.40 per trade on average. Even though the win rate is close to 50%, the losses are slightly larger than the wins, producing a negative expectancy. Over 500 trades, this strategy would lose approximately $9,200 — a slow bleed that might not be noticed until significant damage has already been done. The calculator makes this negative edge visible immediately.
Tips and Limitations
Calculate Expectancy from Real Data, Not Guesses
The calculator is only as accurate as the inputs you provide. If you estimate your win rate at 55% but your actual record shows 48%, your real expectancy is dramatically worse than what the calculator reports. Track every trade, compute your actual win rate and actual average win/loss, and use those numbers. The goal is an honest assessment of your strategy, not a flattering one.
Include All Costs
Commissions, spreads, slippage, and borrowing costs all reduce your expectancy. A strategy with a gross expectancy of $30 per trade and $12 in round-trip costs has a net expectancy of only $18 — a 40% reduction in your edge. Factor in all costs to get a true picture of what each trade is worth to you.
Expectancy Is Not a Guarantee
A positive expectancy of $50 per trade does not mean you will make $50 on every trade, or even on average over 50 or 100 trades. Variance can produce extended periods where results are far worse than the expectancy. The expectancy only becomes reliable over hundreds or thousands of trades. Think of it as the long-run average — it tells you the direction and magnitude of your edge, but not the path you will take to realize it.
Combine with Position Sizing
Expectancy tells you whether you have an edge; position sizing tells you how much to risk to maximize that edge while staying safe. A positive expectancy with reckless position sizing can still blow up an account. Use our position size calculator alongside expectancy to determine how much to risk per trade, and our risk-of-ruin calculator to see how your sizing affects your probability of account survival.
Frequently Asked Questions
What is trading expectancy?
Trading expectancy is the average amount you expect to win or lose per trade, expressed in dollars, when a strategy is applied over a large sample of trades. It is the definitive measure of whether a trading system has an edge — a positive expectancy means you make money on average, a negative expectancy means you lose money on average, and a zero expectancy means the strategy is break-even. Expectancy combines your win rate and your average win/loss ratio into a single number that tells you, in plain dollar terms, what each trade is worth to you on average.
Why is expectancy more important than win rate?
Because win rate alone tells you nothing about profitability without knowing the size of the wins relative to the losses. A strategy with a 70% win rate might lose money if the 30% of losing trades are much larger than the 70% of winning trades. Conversely, a strategy with a 40% win rate can be highly profitable if the 40% of winning trades are much larger than the 60% of losing trades. Expectancy captures both dimensions — win rate and win/loss size — in a single metric, which is why it is the more complete and useful measure of a strategy's edge.
What does a positive expectancy look like?
A positive expectancy means that, on average, each trade makes money. If your expectancy is $50 per trade, that means that over a large sample of trades, you average a $50 profit per trade regardless of which specific trades were winners or losers. A positive expectancy of $50 does not mean every trade makes $50 — it means the weighted average of your wins and losses produces $50. You might win $200 on some trades and lose $100 on others, but if the math works out to a $50 average, you have a positive edge.
Can a positive expectancy strategy still lose money over short periods?
Absolutely, and this is one of the most important concepts in trading. A positive expectancy guarantees profitability only over an infinite sample of trades. In the short term — which for most traders means hundreds or even thousands of trades — variance can produce extended losing streaks that overwhelm a positive expectancy. A strategy with a $20 per trade expectancy can easily experience a 50-trade losing streak at some point. The positive expectancy ensures that over the long run, those losses will be recovered, but the short-term pain can be severe enough to cause a trader to quit before the long run arrives.
How many trades do I need to calculate a reliable expectancy?
Most statisticians consider a minimum of 100 trades necessary for a rough estimate of expectancy, with 300 to 500 trades providing a more reliable figure. With fewer than 100 trades, the sample is too small to distinguish between a genuine edge and random noise. A strategy that shows a positive expectancy over 30 trades might simply be lucky, and the true expectancy might be negative. Over 300 or more trades, the law of large numbers kicks in and your calculated expectancy converges toward the true expectancy of the strategy.
What is the difference between expectancy and edge?
They are essentially the same concept. A positive expectancy IS an edge. The word 'edge' is used more casually in trading conversation — 'I have an edge on this setup' — while expectancy is the mathematical quantification of that edge. Edge is qualitative; expectancy is quantitative. A trader with a positive expectancy of $30 per trade has a defined edge of $30 per trade. The edge is real only if the expectancy remains positive over a large enough sample to be statistically meaningful.
How does expectancy relate to the Kelly Criterion?
Expectancy tells you whether you have an edge; the Kelly Criterion tells you how much to bet to maximize that edge. They work together: first you calculate expectancy to confirm your strategy is profitable, then you use the Kelly Criterion (or a fractional version of it) to determine optimal position size. A positive expectancy is a prerequisite for the Kelly Criterion to be meaningful — if expectancy is negative, Kelly says do not bet at all. Our Kelly Criterion calculator uses your win rate and reward-to-risk ratio (the same inputs as expectancy) to determine optimal sizing.
Should I include commissions and fees in my expectancy calculation?
Yes, absolutely. Commissions and fees are real costs that reduce your expectancy. A strategy with a gross expectancy of $45 per trade and $10 in round-trip commissions has a net expectancy of only $35 per trade. If you ignore commissions, you overstate your edge, which leads to over-sizing your positions and a higher-than-expected risk of ruin. Always calculate expectancy net of all trading costs — commissions, spreads, slippage, and any other expenses that are part of executing the strategy.
Can expectancy be negative and I still make money?
No, not over the long run. A negative expectancy means you lose money on average per trade. If your expectancy is −$15 per trade, you will lose approximately $15 for every trade you take, regardless of which trades are winners. You might have profitable days, weeks, or even months due to variance, but over a large sample of trades, a negative expectancy guarantees net losses. The only way to make money with a negative expectancy is to stop trading the strategy — which is exactly what the calculator is designed to help you decide.