Moving averages: calculation, context and limitations
Learn what a moving average shows, how settings change it and why signals can fail.
What is being averaged?
A moving average smooths a sequence of observations over time. On a price chart, its output depends on the selected period, price input and calculation method. A 20-period average on hourly candles represents a different window from one on daily candles.
MetaTrader offers simple, exponential, smoothed and weighted methods. Check the settings before comparing two lines or interpreting a saved chart.
Simple and exponential methods
A simple moving average gives equal weight to the selected observations. An exponential moving average gives greater weight to recent observations. The latter generally responds more quickly to a new price change, but responsiveness is not the same as reliability.
Neither method is universally better. The chosen settings must be evaluated with the market, timeframe and purpose of the analysis.
Crossovers describe a change in historical averages
A short-period line crossing a longer-period line describes how two summaries of past data now relate. It does not prove that a new trend will continue.
In a range, repeated crossings can generate frequent reversals or “whipsaws.” Spreads, commission and financing can materially change the result of a rule based on those signals.
Several indicators can repeat the same information
A ribbon of moving averages or a second indicator may look like confirmation while relying on much of the same underlying price data. More lines do not automatically provide independent evidence.
If you combine timeframes or indicators, define what each contributes and how conflicting signals will be handled. Avoid changing the interpretation after seeing the outcome.
Test the rule, not just the chart
Document period lengths, input prices, calculation method, entry and exit rules and transaction costs. Use data outside the period used to choose the settings.
Moving averages lag the observations they summarise. Historical results, especially after repeated optimisation, do not guarantee future performance. Review position risk separately from the indicator signal.
Further reading
This guide explains concepts and ways to organise your research. It is not a recommendation to trade, a personal allocation plan or a promise of returns. Read the Terms of Business and your account conditions.