What it means
Profit factor = gross profit ÷ gross loss. Above 1 the method made money over the sample; below 1 it lost.
Why traders use it
It combines win rate and win size into one number that is easy to compare. Many traders treat values above about 1.3–1.5, after costs and on a large sample, as worth further testing.
Chart examples
Profit factor from the same 30 trades
How to identify it objectively
- 1Sum all winning trades (gross profit).
- 2Sum all losing trades as a positive number (gross loss).
- 3Divide.
- 4Report with the number of trades and the date range.
Bullish use
- 1Profit factor applies to the method as a whole.
- 2Compare long-only and short-only profit factors.
Bearish use
- 1A profit factor below 1 after costs means the rule loses money over the sample.
What confirms it
- Stable across different periods.
- Costs included.
What invalidates it
- A few huge winners create the whole result.
- Tiny sample.
How a hypothetical setup is built
Entry
Not an entry rule: a measurement.
Stop
Record actual losses including slippage.
Target
Compare profit factor for different exit rules.
A hypothetical illustration of how the concept is turned into a plan, not a recommendation. Practise it on a paper account first.
Related concepts
- Risk Management & StatisticsExpectancy
- Risk Management & StatisticsMaximum Drawdown
- Risk Management & StatisticsLook-Ahead Bias and Overfitting
Historical testing
The example uses the same made-up 30-trade sequence as the expectancy lesson: gross profit 22R, gross loss 19R, profit factor ≈ 1.16. It shows arithmetic only.
Limitations: when it fails
- Says nothing about drawdown or streaks.
- Small samples can show very high values by luck.
- One outlier can dominate.
Knowledge check
Pick an answer to see the explanation. Nothing is saved.