How we score an Expert Advisor
Every score comes from the Strategy Tester report the developer or a user provides. The rules are fixed and written here, so you can check them against any report yourself.
Where the numbers come from
We read the HTML report from MetaTrader 4 or MetaTrader 5, including the trade history. Commission and swap are reconciled with the profit, so the figures match the report. Each report records how many of its trades could be read, and the analysis says so when some are missing.
Performance score
The performance score rewards results that are large relative to the risk taken and that rest on enough trades. It combines the profit factor, the expected payoff as a percentage of the deposit, the recovery factor, the number of trades, and a robustness check. The robustness check asks whether the result still looks sound when the trades are examined more closely. A report with too few trades cannot score well, however good its early figures look.
Risk score
The risk score measures how much the EA can lose. It uses the drawdown from the report, a stress estimate of the drawdown at the 95th percentile of outcomes, the profit factor, and how concentrated the profit is in the five best trades. It also flags structural patterns, such as lot sizes that grow after losing trades. A high risk score means the EA needs careful lot sizing and a large account.
The verdict
The verdict is a plain label based on both scores. A verdict needs at least 30 closed trades. The strongest label, a strong candidate, needs at least 100 trades and a robustness check of 60 or more. An EA with strong raw numbers but weak robustness stays on watch, because those numbers are not yet proven. The verdict appears only in the full report.
The written summary
The summary is generated from the metrics of the report. The written findings are checked against the same figures: any finding that quotes a number missing from the report is dropped before it is shown.
The developer score
A developer's score is the average performance score of the latest public analysis of each of their active Expert Advisors. It is provisional until three Expert Advisors have been analysed. It reflects performance only. Robustness and risk are part of the full report and are not used in the developer score.
What the scores cannot tell you
A backtest uses fixed settings on past prices. Live trading differs because of spreads, slippage, broker and server changes, and changing market conditions. Optimised settings can make a backtest look better than the EA will perform. The scores help you ask better questions before you trade; they do not answer whether an EA will make money. This is informational only and not investment advice.