Signal line (MACD)
The signal line is the 9-period exponential moving average of the MACD line, whose crossovers with it serve as buy or sell signals.
The MACD is made of two lines: the MACD line itself (the difference between the 12-period and 26-period EMAs of price) and the signal line, which is the 9-period exponential moving average of the MACD line. By smoothing the MACD, the signal line filters out its jitters: it reacts with a slight lag, which helps distinguish a genuine momentum inflection from a mere wobble.
MACD / signal crossovers
The classic signal is the crossover: when the MACD line moves above the signal line, momentum is improving (bullish reading); when it drops below, momentum is deteriorating (bearish reading). Crossovers occurring far from the zero line, after an already extended move, are considered weaker than those happening near zero. In Screener.Trading, a screener rule can detect the MACD line crossing above its signal line, and an automated scan can e-mail you every time a new occurrence appears at candle close.
In a trendless market, MACD/signal crossovers multiply and lose reliability: add a trend filter (for example price above a long moving average) before acting on them.
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- FeatureThe multi-indicator, multi-timeframe screenerCombine technical indicators, timeframes and comparison operators to keep only the assets that match your strategy exactly.
- FeatureAutomated scans: your screeners on autopilotBots watch the market for you: they re-run your screeners at every candle close and e-mail you the moment an asset matches.
- IndicatorMACD (Moving Average Convergence Divergence)A momentum indicator built on two exponential moving averages: its crossovers and histogram measure the acceleration and exhaustion of trends.
- IndicatorExponential Moving Average (EMA)A moving average that gives more weight to recent candles: it hugs price more closely than the SMA and reacts earlier to trend changes.
- GlossaryMACD histogramThe MACD histogram plots the gap between the MACD line and its signal line, thereby measuring whether momentum is accelerating or fading.
- GlossaryTimeframeA timeframe is the duration each candle on a chart represents (from one minute to several months) and sets the horizon of the analysis.
- GuideSetting up trading alerts with autoscansLet your screeners watch the market for you: create an autoscan in two clicks, get an e-mail as soon as an asset matches, and avoid noise with a few best practices.
- GuideBuilding your first screener, step by stepHow to turn a strategy idea into objective rules, pick the right asset universe, read scan results and iterate until you get a genuinely actionable list of opportunities.