Formula
The formula is displayed so the result can be checked independently. PreBreakout does not use a hidden scoring model on this page.
Worked hypothetical example
With a hypothetical 45% win rate, average win of 2R and average loss of 1R, expectancy is 0.35R per modeled outcome.
Important: the numbers are fictional and are not associated with a security, issuer or current market price.
What this calculator does not tell you
- The quality of the result depends entirely on the assumptions you enter.
- Past results, if used as inputs, may not persist in the future.
- Positive modeled expectancy is not a recommendation to trade a strategy.
Market execution can differ from arithmetic inputs because of spreads, gaps, slippage, order types, broker constraints and other factors. This tool does not attempt to model those effects unless an input explicitly asks for a value.
How to use it for learning
Change one input at a time and observe how the result changes. This is especially useful for understanding sensitivity: wider stop distance changes position-size arithmetic, a taller pattern changes a measured-move result, and a larger reward-to-risk ratio changes the theoretical break-even win rate. The exercise is about the formula, not about identifying a trade.