Spread Monitor - expert pour MetaTrader 5

Spread Monitor is a single-file MQL5 Expert Advisor that shows the trading spread of the attached symbol on a colour-coded panel in the chart corner. Spread is the difference between the ask and bid price, and MetaTrader 5 reports it as an integer number of points through SYMBOL_SPREAD. The utility reads this value on each refresh, stores it in a fixed-size rolling buffer, and recalculates four statistics on that history: the current spread, the average, the minimum, and the maximum. It also counts how many stored samples exceed the warning level, so the trader can see how often the spread is high on this symbol and not only at one moment. The status row turns red when the current spread is above the warning level and green otherwise.

The refresh is throttled to a configurable interval, so the panel does not rebuild on every tick. The history is kept in memory and resets when the EA is removed, the symbol is changed, or the terminal restarts. The panel objects carry a fixed name prefix, so the EA removes only its own objects on exit and leaves other chart objects alone.

The utility does not place, modify, or close any order, and it does not block trading by other programs. Its inputs are the warning level in points, the number of samples kept, the refresh interval in seconds, the panel corner, and the horizontal and vertical offsets. It is intended for traders who want to see spread behaviour during the session, before deciding when to trade.