EA works on demo but not live

Causes, most likely first

1. Demo fills are not real fills

A demo server fills at the quoted price with unlimited liquidity. Live execution supplies neither. Every entry and exit is slightly worse, and the difference compounds across hundreds of trades — see slippage.

2. The demo account has a different spread

Demo accounts frequently mirror a raw-spread feed while the live account is standard, where cost is folded into the quote. Compare the two directly in Market Watch rather than assuming they match. On a short-target strategy this alone can flip the result.

3. The strategy is spread-sensitive and was never tested against a real one

Our own measurement puts median XAUUSD spread at $0.16 on a raw account, but the tail is what matters and a standard account looks nothing like it. See the published spread data.

4. Nothing changed except the sample

This is the uncomfortable one. A demo run of thirty trades and a live run of thirty trades are two small samples of the same distribution, and they will differ. Before concluding the live account is broken, check whether the difference is larger than the sample size supports.

Why this happens

The demo-to-live drop is real, well documented and systematically largest for the strategies most often sold — scalpers taking small targets, where execution quality is the entire margin. A position strategy holding for days barely notices.

That is why demo results should be read as evidence the software runs, not as evidence the strategy works. They confirm the logic executes, orders form correctly and nothing crashes overnight, which is worth knowing and is not a track record.

It is also why we publish the continuous-run figures rather than the flattering windowed ones, and the worst drawdown rather than the best — see demo account results.