tool · Performance & testing
Trade Expectancy Calculator: Probability, Payoff and Cost
Expectancy is a probability-weighted average outcome. This tool combines an assumed win rate, average winning amount, average losing amount and per-trade cost without treating the result as a forecast.
Key points
- Win and loss amounts are positive magnitudes before the separately entered costs.
- The model treats each non-winning outcome as a loss.
- A positive model value does not establish a reliable future edge.
Trade expectancy calculator
The starting numbers are illustrative inputs. Replace them with a consistent scenario. Calculations run in your browser; no account connection or live market data is used.
Formula and boundaries
Expected amount per trade = win probability × average win − loss probability × average loss − average cost per trade.
- Win probability and outcome averages are assumed inputs, not forecasts.
- Average win/loss amounts must use one currency and exclude the separately entered cost to avoid double counting.
- This two-outcome model treats every non-winning trade as a loss; represent breakeven trades consistently before using it.
State the observation before the average
A trade might mean a completed position, an entry-to-exit campaign or a single fill. Choose one definition and use it throughout the sample. Counting every partial winning exit as a win while grouping all losing exits into one loss distorts both the win rate and average payoff. This calculator expects one coherent two-outcome definition.
The formula is p × average win − (1 − p) × average loss − average cost, where p is the win rate divided by 100. It reports the expected arithmetic amount per trade and the corresponding total across 100 hypothetical trials with those same inputs. MetaTrader's testing report distinguishes payoff and outcome statistics. Platform definitions still need checking before numbers are imported.
Reproduce the sample calculation
Assume a win rate of 45%, gross average win of 200, gross average loss of 100 and average cost of 5. The winning contribution is 0.45 × 200 = 90. The losing contribution is 0.55 × 100 = 55. Subtracting the cost gives 90 − 55 − 5 = 30 per trial under the model.
The 100-trial arithmetic expectation is 3,000. That is neither a promised ending balance nor a compounded return. The actual sequence can produce a different total and deep temporary losses. If the assumed win rate falls to 35% while the other inputs remain fixed, expectancy becomes 70 − 65 − 5 = 0. A ten-percentage-point input change removes the entire modeled advantage.
Avoid cost and sample mismatches
If your journal's win and loss amounts already include all costs, enter zero in the separate cost field. Otherwise subtracting the same expense again understates the result. If charges differ between winners and losers, calculate a suitable overall average or use a more detailed outcome model. The tool has one cost input rather than separate conditional fee distributions.
Breakeven outcomes require a deliberate convention. Combining them with losses changes the losing-outcome count and average magnitude. Alternatively, a three-outcome probability calculation can keep them separate, but this interface does not do so. Do not silently drop them while retaining a win rate computed over all trades.
Interpretation and failure modes
The win-rate input must lie from 0% through 100%; amounts and costs cannot be negative. Zero payoff values are permitted because they can describe a degenerate example, though they may not represent a useful trading model. Values that overflow the supported numeric range are rejected.
Estimates from a short, selected or correlated sample can be unstable. Check the number of observations, data dates, excluded accounts, changes to execution and whether the inputs came from research or an untouched evaluation period. The output describes the assumptions supplied today; it does not recommend a trade, identify a signal provider or establish that copied accounts will share the source account's outcome distribution.
Questions and answers
Is the 100-trial result a profit prediction?
No. It multiplies the modeled arithmetic expectancy by 100. It does not simulate a sequence, compound capital or establish that the assumed probabilities will persist.
Should commissions be included twice?
No. Enter gross win and loss magnitudes with a separate cost, or use consistently net outcome amounts and zero additional cost. Document the convention.
Sources and further checks
Use the current source for your exact instrument, account and platform. Referencing a general specification does not establish support for every TradeCopier workflow.
- MetaTrader 5: testing report definitions · Checked September 19, 2026
Found an error? Send a correction with this page's address and a primary source. See our editorial standards for how we handle examples, claims and revisions.
