How much gold history do I need for a reliable backtest?

At least three years, which on XAUUSD reliably spans a trending phase, a compressive range and at least one shock event. Shorter windows risk sampling a single regime and mistaking it for a general edge.

Do I need tick data to backtest a gold scalp?

For any strategy with a stop under roughly $5 per ounce, yes. Bar data cannot tell you whether the stop or the target was hit first within a candle, which quietly resolves close trades in the backtest engine's favour.

Why does my gold backtest outperform my demo results?

Almost always spread, slippage and rollover cost that were modelled too generously, or a regime present in demo trading that was under-represented in the backtest history. Recheck the cost model by session before assuming execution is the problem.

Should I test the same rules on XAUEUR or XAUGBP?

It is a useful cross-check. A genuine gold behaviour usually leaves a similar trace in gold priced in other currencies; if the edge disappears entirely, the effect may be dollar-side rather than a real gold pattern.

What is walk-forward testing and why does it matter for gold?

It means finalising rules on an early data window and testing them unchanged on the next window forward in time, repeated across the sample. It catches curve fitting that a single in-sample backtest cannot, because gold's regime shifts make in-sample results unusually easy to over-fit.

Can a backtest replace demo forward testing?

No. A backtest cannot reproduce live spread widening, slippage, requotes or your own execution behaviour. It establishes that a pattern exists; the demo phase establishes what it actually costs to trade.

BACKTESTING GOLD HONESTLY

Backtesting a gold strategy honestly requires tick-level or reconstructed data for stops under about $5 per ounce, explicit spread modelling that distinguishes the $0.15–$0.35 London/New York range from the $0.50+ rollover window, and an explicit swap schedule pulled from the actual execution broker.

Results must be split by market regime — trending, ranging and shock periods — rather than reported as a single blended figure across calendar dates, since XAUUSD cycles between these regimes and a rule set profitable in one can be unprofitable in another.

Walk-forward validation across sequential rolling windows, plus a final untouched holdout period of at least six months, catches the curve fitting that a single in-sample backtest cannot, and produces the realistic cost-adjusted expectancy that demo forward testing should then be measured against.