A moving average plots the average price over a set period, smoothing out the day-to-day jitter so the real trend stands out clearly.
A moving average (MA) is the average closing price over a fixed number of recent periods — say, the last 50 days — recalculated fresh every single day as the window "moves" forward one period at a time. Plot that rolling average as its own line on the chart, and it smooths away the day-to-day zigzags to reveal the underlying trend far more clearly than the raw price line alone.
The most common type is the simple moving average (SMA), which weights every day in the window equally. A related version, the exponential moving average (EMA), weights recent days more heavily so it reacts faster to new information — both do the same basic job of smoothing, just with a different lag/responsiveness trade-off.
Two things make moving averages especially useful: they can act as dynamic support or resistance (price often bounces off a rising 50-day or 200-day average the same way it bounces off the fixed levels from the last lesson), and comparing a short-term average against a long-term one reveals trend-strength crossovers — the famous "golden cross" and "death cross" covered below.
Nothing about the underlying data changed between these two charts — only how it's displayed. That's the entire value of a moving average: it trades a small amount of lag (it reacts a bit slower than raw price, since it's an average of the past) for a much clearer read on direction.
Real S&P 500 50-day and 200-day simple moving averages, calculated from actual daily closes.
| Date | Close | 50-day SMA | 200-day SMA | Signal |
|---|---|---|---|---|
| Mar 14, 2022 | $4,173.11 | $4,463.96 | $4,467.00 | Death cross — 50 crosses below 200 |
| Feb 2, 2023 | $4,179.76 | $3,953.61 | $3,951.58 | Golden cross — 50 crosses above 200 |
On Mar 14, 2022, the S&P 500's 50-day average ($4,463.96) slipped below its 200-day average ($4,467.00) — a "death cross," a classic (if lagging) bearish signal, arriving as the 2022 bear market was getting underway. Almost a year later, on Feb 2, 2023, the pattern flipped: the 50-day average ($3,953.61) crossed back above the 200-day ($3,951.58) — a "golden cross" — right as the index was beginning the recovery documented in the Trend Lines and Support & Resistance lessons. Note both crosses happened well after the actual price turns (Mar 14 close was already down from the Jan high; Feb 2 was already off the Oct low) — that lag is the trade-off for the smoothing.
Enter 5 sequential daily prices and see a 3-day simple moving average plotted alongside the raw, jagged price line.
Model: a 3-day simple moving average needs 3 data points, so the first plotted MA value covers Days 1-3, the next covers Days 2-4, and so on — that's why the smoothed line starts 2 days later than the raw price line.
Answer all five, then hit "Check My Answers" to see how you did. Get one wrong? No problem — the explanation will show you exactly why.
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Candlesticks, trend lines, volume, support & resistance, and moving averages — that's the full toolkit for reading any price chart. Next, put it into practice or explore another track.