Ask a struggling trader why they're losing and you'll usually hear a story: the market's choppy, the news was against them, their broker slipped the fill. Ask them for their expectancy per trade and you'll usually get silence. That gap — between the story and the number — is where most edges quietly die.
An "edge" isn't a feeling or a strategy you believe in. It's a measurable, positive expected value: over a large enough sample, your process makes money. The good news is that your own trade history already contains the answer. You just have to compute it honestly.
Why win rate lies on its own
Win rate is the most quoted and least useful number in trading. A 70% win rate sounds elite — and will still blow up your account if your average loss is three times your average win. A 35% win rate sounds hopeless — and can compound beautifully if your winners run four times your losers. Win rate only means something when you pair it with risk-to-reward (R:R): the size of your average win versus your average loss.
The two combine into expectancy — the average amount you make (or lose) per trade:
Expectancy = (Win rate × Average win) − (Loss rate × Average loss)
If that number is positive, you have an edge. If it's negative, you don't — no matter how good any single month looked.
A worked example
Take a trader with a 45% win rate who feels like a loser because "I'm wrong more than I'm right." But their average win is $220 and their average loss is $120:
- Wins: 0.45 × $220 = +$99 per trade on average
- Losses: 0.55 × $120 = −$66 per trade on average
- Expectancy: $99 − $66 = +$33 per trade
This trader has a genuine edge despite being "wrong" most of the time. Now flip it: a 60% win rate with a $90 average win and a $160 average loss produces an expectancy of (0.60 × $90) − (0.40 × $160) = $54 − $64 = −$10 per trade. They win more often and lose money. The win rate flattered them; the expectancy told the truth.
The three numbers to pull from your tradebook
You can compute a rough edge with nothing more than a spreadsheet of closed trades:
- Win rate — winning trades ÷ total trades.
- Average win and average loss — the mean P&L of your winners and of your losers, separately. Their ratio is your realised R:R.
- Expectancy — plug both into the formula above. Multiply it by your number of trades and you have your expected P&L for the period.
One more number sharpens the picture: profit factor — gross profit ÷ gross loss. Above 1.0 you're net positive; below 1.0 you're not. It's a fast sanity check on the expectancy you just calculated.
Edge is not spread evenly — map it
Here's the part that changes how people trade: your edge is almost never uniform. You may have a strong, repeatable edge in two instruments and be quietly handing it all back in five others you trade out of boredom. A single account-level expectancy hides this completely.
The fix is to rank every instrument you've traded by P&L and win rate. Most traders are shocked to find that a handful of symbols carry the entire account, while a long tail of "just having a look" trades bleeds steadily. Cut the tail and the same trader is suddenly profitable — not because they found a new strategy, but because they stopped diluting the edge they already had.
Know My Trade computes your win rate, average win/loss, R:R, expectancy per trade, profit factor and max drawdown for every year of data you upload — then maps your edge across every symbol you've traded, ranked by P&L and win rate. You see exactly which instruments fund your account and which ones leak, instead of guessing from a single blended number.
What to do with the answer
If your expectancy is positive, your job is protection: don't dilute it with low-conviction trades, and size consistently so one bad bet can't erase a month of edge. If it's negative, resist the urge to add a new indicator. First find where the negative expectancy lives — usually a specific instrument, style, or time of day — and remove that, before you touch anything that's working.
Either way, the starting point is the same: stop quoting your win rate and start computing your expectancy. The market doesn't pay you for being right. It pays you for positive expected value, repeated with discipline.