200-Day Moving Average

200-day moving average: the short answer

The 200-day moving average (200-DMA) is the average closing price of a security over its last 200 trading sessions, recalculated every day. It smooths short-term noise into one slow-moving line. Price above it is widely read as a long-term uptrend bias; price below it flags caution or a downtrend.

How the 200-day moving average is calculated

A simple moving average (SMA) adds up the closing prices of the last 200 sessions and divides by 200. Each new day, the oldest close drops off and the newest close joins — the window slides forward, which is why it's called a moving average. Because 200 sessions is roughly ten months of trading, the line moves slowly and ignores day-to-day chop.

Some traders prefer an exponential moving average (EMA), which weights recent prices more heavily so the line turns a bit sooner. Both answer the same question — what has the trend been over the long haul — just with different lag. The 200-day is the default long-term lens; its faster cousins, the 50-day and 20-day, track the intermediate and short-term trend.

Above the line vs. below the line

The appeal is simplicity. One glance answers a blunt question: is this thing in a long-term uptrend or not?

• Price above a rising 200-DMA — the classic healthy-uptrend read. Buyers have controlled the tape over a long horizon, and pullbacks toward the line often find support.
• Price below a falling 200-DMA — a caution flag. Rallies into the line frequently stall as it acts as overhead resistance.
• Price chopping across a flat 200-DMA — no durable trend. This is where the signal is weakest and whipsaws are most common.

The slope of the line matters as much as which side price is on. A rising 200-DMA and a falling one tell very different stories even at the same price level.

The golden cross and the death cross

Two widely-quoted crossover events involve the 200-day line:

• Golden cross — the 50-day moving average crosses above the 200-day. Read as a bullish shift, a shorter-term uptrend gaining enough strength to turn the long-term picture.
• Death cross — the 50-day crosses below the 200-day. Read as a bearish shift and often cited in financial headlines.

Both make dramatic copy, but honesty demands a caveat: because moving averages lag, these crosses confirm a move that's already well underway rather than predict a new one. They can arrive near a bottom just as easily as a top. Treat them as descriptions of trend that has already changed, not forecasts.

Strengths and limits

The 200-DMA earns its popularity honestly: it's objective, free of curve-fitting, and it keeps you on the right side of long, sustained trends. Trend-following research going back decades suggests that a simple "own it only above the 200-day" rule has, on average, kept traders out of the deepest stretches of major bear markets — though it does so imperfectly and pays for the protection with whipsaws.

The weaknesses are real. In sideways, range-bound markets it flip-flops across the line and fires false signals. It always lags, so you give back some gains near tops and enter late off bottoms. And a level watched by millions is not a secret edge; it's context. Used alone, the 200-DMA is close to a coin-flip in choppy tape. Its value comes from combining it with breadth, relative strength, and the trend of the broader market.

How Coil reads it

Coil reads the market top-down — the index tape first, then sectors, then individual names — and the 200-day moving average is one input into that first gate, not a standalone signal. Before Coil considers buying weakness in any name, it wants the broader tape pointed the right way: a benchmark holding above its long-term trend is one piece of evidence that the environment favors owning leaders rather than sitting in cash.

But it's deliberately just one piece. A single line that everyone watches doesn't decide anything on its own — the index gate blends trend, breadth, and momentum so no lone indicator can wave the whole board green or red. On individual names, the 200-DMA informs the support map Coil uses to time pullback entries, since price so often reacts near it. You can see exactly how these tape conditions feed the daily scoring on the how it works page. And when the tape sits below trend, Coil's answer is simple and unglamorous: cash is a position. None of this is investment advice — Coil is educational, rules-based software you run yourself, not a recommendation to buy or sell any security.

People also ask

What does it mean when a stock is above its 200-day moving average?

It signals a long-term uptrend bias — buyers have controlled the price over roughly the last ten months. Many traders treat the line as support and view being above it as a condition for holding or buying. It's context, not a guarantee the uptrend continues.

Is the 200-day moving average a good buy or sell signal on its own?

Not reliably. It works well in strongly trending markets but whipsaws badly in sideways ranges, and it always lags. Most disciplined approaches use it as one filter alongside breadth, relative strength, and the broader market trend rather than as a standalone trigger.

What is the difference between a golden cross and a death cross?

A golden cross is when the 50-day moving average crosses above the 200-day, read as bullish. A death cross is the opposite — the 50-day crossing below the 200-day, read as bearish. Both confirm a trend change already underway rather than predict one.

Should I use the simple or exponential 200-day moving average?

Both are valid. The simple (SMA) weights all 200 days equally and is the most-quoted version. The exponential (EMA) weights recent prices more, so it turns slightly sooner. The difference is small at 200 sessions; pick one and stay consistent.

How many days of data do you need for a 200-day moving average?

At least 200 trading sessions — roughly ten calendar months, since markets are closed on weekends and holidays. Newer stocks and recent IPOs won't have a valid 200-DMA until they've traded that long, which is one reason it's a long-term-only tool.

Related terms

Trend following · Relative strength · Market breadth · Trailing stop · full glossary →