Expert advisor in gold trading

An expert advisor (EA) is an automated trading program written in MQL4 or MQL5 that runs on a MetaTrader chart. It reads prices and indicators on each tick or bar, applies its rules and sends orders without manual input. Gold is one of the most popular symbols for EAs because of its range and volatility.

How it applies to gold trading

An EA is only as good as its logic and its risk controls. Many commercial gold EAs rely on grids, martingale sizing or averaging down, which show smooth equity curves until a strong one-way move, then lose most of the account. Others are honest systems whose edge disappears with real spreads, slippage and swaps. A robust EA uses a stop-loss on every trade, sizes from a fixed risk and has been tested out of sample and on a demo or small live account.

Practical issues matter too: the symbol suffix, filling mode, server time and the daily break all trip up EAs moved to a new account. Most run on a VPS so they keep working while your computer is off.

Worked example

Example (hypothetical numbers): a backtest shows an EA making 4% a month with a 6% maximum drawdown. Adding a realistic $0.30 spread and $0.20 average slippage on 200 trades of 0.10 lots costs 200 × 0.50 × 100 × 0.10 = $1,000, turning a $1,200 backtest profit on a $10,000 account into $200.

A common mistake

Buying an EA on the strength of a short backtest or screenshots. Ask for out-of-sample results, the worst drawdown and whether it uses a stop on every trade.

See also: Backtest, Martingale, Grid trading, Curve fitting.

Frequently asked questions