Moving averages explained

A moving average turns noisy prices into a smoother line. It is a description of past data, not a forecast. Here is what it calculates and how to read it without overclaiming.

A moving average is the average closing price over a fixed number of periods. On a daily chart with a 20-period average, each point is the mean of the last 20 daily closes. Because the window moves forward one bar at a time, the line follows price slowly instead of reacting to every single move.

Simple versus exponential

A simple moving average (SMA) gives every period in the window the same weight. An exponential moving average (EMA) gives more weight to recent closes. The EMA therefore turns sooner, but that also means it reacts more strongly to noise. Neither calculation knows where price is going; both summarise what has already happened.

Why periods such as 5, 20 and 60 are common

Different periods look at different time horizons. A 5-period average on daily data follows price closely. A 20-period average smooths out roughly a month of trading. A 60-period average smooths out about a quarter. These windows are easy to reason about; the numbers are not magic.

Traders and analysts often show several averages together to compare short, medium and long timeframes. The lines are context, not instructions.

Crossovers and lag

When a short average crosses above a longer average, the short-term average is higher than the longer-term average. That is a factual description of recent closes. It is not a guarantee that price will keep rising. Crossovers happen after a move has already begun, and they can whipsaw in sideways markets.

Lag is built into the calculation. A 60-day average cannot include today’s news until today’s close is part of its window. Choosing a period is partly a choice about how much lag you are willing to accept.

Use averages as questions, not answers

Useful questions include: is price above or below a medium-term average? Is the average itself rising or falling? Are several timeframes aligned or pulling in different directions? These questions help organise a chart review; they do not remove uncertainty.