Risk-to-Reward Ratio and Trading Expectancy Explained
See why win rate alone cannot describe a strategy and learn to combine average wins, losses and costs into an expectancy estimate.
A strategy can win often and still lose money, or win less often and remain profitable. The difference is the relationship between the size and frequency of wins and losses. Risk-to-reward describes the planned loss relative to the potential gain on one trade. Expectancy estimates the average outcome across many trades using actual results. Both are useful, but neither should be evaluated without trading costs and a sufficiently large sample.
From trade plan to expectancy
If a trade risks one unit to target two units, its planned reward-to-risk is 2:1. The realized ratio may differ because of partial exits, slippage or early closures. A simple expectancy calculation multiplies win rate by average win, multiplies loss rate by average loss and subtracts the second value from the first. Commission, spread, funding and other costs should be deducted. A positive historical estimate is not a guarantee; it is evidence about the tested sample.
Avoid optimizing a single metric
Pushing targets farther away may improve the advertised ratio while sharply reducing the chance of reaching them. A high win rate can hide occasional oversized losses. Measure average realized win and loss, maximum adverse movement, consecutive losses and performance by market condition. Use the same entry and exit rules during testing and live execution. Review expectancy over rolling samples rather than after every trade.