MACD (Moving Average Convergence Divergence)

MACD has three components that together paint a picture of trend direction and momentum strength.

MACD Line = 12-period EMA minus 26-period EMA. When the 12 EMA (fast) is above the 26 EMA (slow), the MACD line is positive — the short-term trend is bullish. When it's below, the MACD line is negative — short-term trend is bearish. The further the MACD line moves from zero, the stronger the trend.

Signal Line = 9-period EMA of the MACD line. It smooths the MACD line to generate trade signals. Crossovers between the MACD line and signal line are the primary trading signals.

MACD Histogram = MACD Line minus Signal Line. The histogram turns the crossover into a visual: positive histogram bars mean MACD is above its signal (bullish momentum); negative bars mean MACD is below its signal. Growing bars indicate accelerating momentum; shrinking bars indicate decelerating momentum.

Example: AAPL's 12-day EMA is $192 and its 26-day EMA is $189. MACD line = $3. If the signal line (9-day EMA of MACD) is $2, the histogram is +$1 — bullish and accelerating.

Signal line crossover — The classic MACD trade. Buy when the MACD line crosses above the signal line; sell when it crosses below. This works best in trending markets but generates false signals in choppy, range-bound conditions. Adding a trend filter (price above the 50-day SMA for longs) significantly improves reliability.

Zero line crossover — When the MACD line crosses above zero, the 12 EMA has crossed above the 26 EMA — a more significant trend change than a signal line crossover. Buy when MACD crosses above zero with rising histogram bars; exit when it crosses back below. Slower but more reliable than signal line crossovers.

MACD divergence — The most powerful MACD signal. Bullish divergence: price makes a lower low but the MACD histogram makes a higher low, indicating selling pressure is weakening despite lower prices. Bearish divergence: price makes a higher high but MACD makes a lower high. Divergence signals often precede major trend reversals by 3-10 bars.

Histogram reversal — Watch for the histogram to contract (bars getting shorter) after a strong trend. This indicates momentum is fading even before a crossover occurs. Entering on the first histogram bar in the opposite direction provides earlier entries than waiting for the full crossover.

Standard (12, 26, 9): Gerald Appel's original settings. Works well on daily charts for swing trading. The 12/26 combination captures approximately 2-week and 1-month momentum trends.

Fast (5, 13, 1): More responsive, generates signals earlier. Preferred by day traders on 5-15 minute charts. The shorter periods mean more signals but also more noise. Using a signal period of 1 effectively eliminates the signal line and relies on the MACD line crossing zero.

Slow (19, 39, 9): Filters out noise, captures larger trend moves. Preferred by position traders and weekly chart analysts. Fewer signals but higher quality — particularly good for confirming major trend changes.

Intraday settings: Many day traders use (3, 10, 16) or (5, 34, 1) on 1-5 minute charts. The right settings depend on the average trade holding period: shorter holds benefit from faster settings; longer holds from slower ones. Test settings on your specific strategy before trading live.

MACD and RSI both measure momentum but from different angles.

MACD measures the relationship between two moving averages — it tells you the direction and acceleration of the trend. Best for trend-following entries: entering breakouts, riding momentum, and exiting when momentum fades.

RSI measures the speed and magnitude of recent price changes on a bounded 0-100 scale — it tells you whether a stock is overbought or oversold relative to recent history. Best for mean reversion entries: buying pullbacks in uptrends, selling rallies in downtrends.

Using them together: MACD for direction, RSI for timing. Example: MACD line is above signal and above zero (bullish trend confirmed). RSI pulls back to 40-45 (short-term momentum dip within the uptrend). Enter long on the RSI bounce. This combines trend confirmation (MACD) with entry timing (RSI) — a far more reliable setup than either indicator alone.

The key distinction: MACD is unbounded (can go to any value), making it better for measuring trend strength. RSI is bounded (0-100), making it better for identifying extreme conditions.