Strategy Tester (Backtesting)

A strategy tester runs a trading strategy or Expert Advisor against historical price data to simulate how it would have performed, without risking real capital. It's the standard first step in validating a rules-based strategy before committing to a demo or live account. Backtest results are only as trustworthy as the historical data quality and the honesty of the test — over-optimizing a strategy's parameters specifically to fit past data (curve fitting) tends to produce impressive backtests that fail to hold up on new, unseen price action.