Here is the fact that breaks most new traders' intuition: you can lose more trades than you win and still make money — and you can win the majority of your trades and still go broke. Whether you make money is not decided by how often you are right. It is decided by three numbers working together: win rate, risk-reward, and the thing they produce, expectancy.
Once you can compute expectancy, you stop judging trades by whether they won and start judging your system by whether it is positive. That shift is the difference between gambling and trading.
The three numbers
- Win rate is the percent of trades that make money. Win 45 of 100 trades and your win rate is 45%.
- Risk-reward ratio (R) is how much you make when you win versus how much you lose when you are wrong. Risk $100 to make $200 and your reward-to-risk is 2:1, or "2R".
- Expectancy is the average amount you win or lose per trade once both of the above are baked in. It is the bottom line.
Win rate alone tells you nothing. A 90% win rate is a disaster if the occasional loss is 20 times a win. A 35% win rate is a money machine if winners are 4x losers. You have to hold them together, and expectancy is how.
The expectancy formula
Expectancy per trade = (win rate × average win) − (loss rate × average loss)
Work an example. Say over 100 trades you win 40% of the time, your average winner is $300, and your average loser is $150:
- Win side: 0.40 × $300 = $120
- Loss side: 0.60 × $150 = $90
- Expectancy: $120 − $90 = $30 per trade
A 40% win rate, and you make $30 every time you click the button on average. Over 100 trades that is $3,000. The losing majority never mattered, because the winners were twice the size of the losers.
Now flip it. Win 70% of the time, but your winners are $100 and your losers are $300 (you cut winners early and let losers run — the most common retail pattern):
- Win side: 0.70 × $100 = $70
- Loss side: 0.30 × $300 = $90
- Expectancy: $70 − $90 = −$20 per trade
Seventy percent right, and you lose $20 a trade. This is exactly how confident traders bleed out.
Expressing it in R (the cleaner way)
Pros usually think in R, where 1R is the amount you risk per trade. If you always risk the same $100, then a $200 winner is +2R and a full stop-out is −1R. Expectancy in R terms:
Expectancy (R) = (win rate × average win in R) − (loss rate × 1R)
With a 40% win rate and 2R average winners: (0.40 × 2) − (0.60 × 1) = 0.8 − 0.6 = +0.2R per trade.
That means every trade is worth, on average, one-fifth of what you risk. Risk $100 and you earn $20 of expectancy per trade regardless of the outcome of any single one. R-thinking is powerful because it makes expectancy independent of account size — you can compare a $50-risk trade and a $5,000-risk trade on the same scale.
What this changes about how you trade
- Stop grading yourself on single trades. A losing trade taken with positive expectancy was a good trade. A winning trade taken on a whim was a bad trade that happened to pay. Judge the process.
- Protect your average win. The fastest way to wreck expectancy is cutting winners early and moving stops on losers. Both shrink your R.
- A tiny edge compounds. +0.2R per trade sounds small. Over 500 trades a year at 1% risk each, it is enormous. Consistency of a small positive edge beats chasing a big win rate.
- Know your break-even win rate. For a given risk-reward there is a win rate below which you lose. At 2:1 you break even near 33%; at 1:1 you need above 50%. Trading a 1:1 setup with a 45% win rate is mathematically doomed no matter how good it feels.
Where the numbers come from
You cannot compute expectancy from memory — memory keeps the winners and quietly deletes the losers. It comes from a logged history of trades with real entries, stops, targets and exits. That is the entire point of keeping a Trading Journal: it stores every trade and computes win rate, average win, average loss and expectancy for you, and splits them by setup so you can see which of your strategies is actually positive.
Before the trade, set the R itself with the Risk-Reward Calculator — it turns an entry, stop and target into a clean reward-to-risk number and a break-even win rate, so you only take trades whose math you have already accepted. For leveraged crypto positions, the Crypto PnL & Risk Calculator does the same with liquidation and fees included.
Frequently asked questions
Can I be profitable with a low win rate? Yes. Profitability depends on expectancy, not win rate. With a 2:1 reward-to-risk you only need to win about a third of your trades to break even, and anything above that is profit. Many professional trend traders win well under half their trades.
What is a good expectancy? Any positive expectancy is a real edge; the goal is then to trade it consistently and size it well. In R terms, +0.2R to +0.5R per trade is a strong, realistic edge. Be suspicious of anything far higher over a small sample — it is usually luck or curve-fitting.
What is my break-even win rate? It is 1 ÷ (1 + reward-to-risk). At 1:1 you need 50%; at 2:1 about 33%; at 3:1 about 25%. Trade setups whose realistic win rate clears that bar.
Why does my winning strategy still lose money? Almost always because your average loss is bigger than your average win — usually from cutting winners early and letting losers run past the stop. A high win rate cannot survive a bad payoff ratio. Log your trades and check the two averages.
How many trades do I need before expectancy is meaningful? Treat anything under about 30 trades as noise, and 100+ as a reasonable read. A single week of results tells you almost nothing about your true edge.
Put the math to work
Compute your real win rate, payoff and expectancy automatically in the free Trading Journal, and price the risk-reward of your next setup with the Risk-Reward Calculator. Trade the math, not the feeling.