Trading Expectancy Calculator

FGC Research · Research Tools

An interactive probability calculator for evaluating hypothetical trading outcomes. Adjust the inputs to investigate the effect of different assumptions. Results are mathematical illustrations, not forecasts or verified strategy performance.

Define Your Assumptions

Win rate (%)

Percentage of trades that win

Average winning trade

Use pips, points, or currency units consistently

Average losing trade

Enter positive loss magnitude

Round-trip cost per trade

Same units; includes commissions/spread if applicable

Number of trades

For the linear expectation illustration

Calculated Outcomes

Net expectancy per trade—Input units per trade

Break-even win rate—Including stated costs

Win/loss size ratio—Average win ÷ average loss

Gross profit factor—Before trade costs

Expected total net result—Linear expectation, not a realized outcome

Expected winning trades—Average count; not a prediction

Enter assumptions to calculate the expected mathematical outcome.

How to Interpret the Result

Net expectancy = (win probability × average win) − (loss probability × average loss) − cost per trade. The break-even win rate assumes the stated average win, average loss, and costs remain constant. Positive expectancy does not imply a smooth equity curve or guarantee profit. This calculator excludes changes in position size, nonstationary results, slippage beyond specified costs, and drawdown risk.