MACD (Moving Average Convergence Divergence)¶

OVERVIEW¶

MACD is a trend-following momentum indicator available on all Tapeboard charts. Developed by Gerald Appel in the late 1970s, it measures the relationship between two exponential moving averages to surface changes in momentum, direction, and trend duration. The indicator plots below the price chart and oscillates around a zero line.

Note

MACD is a lagging indicator. Crossover signals fire after the underlying price has already moved a meaningful portion of the anticipated swing. Use it alongside price action, not as a standalone entry trigger.

COMPONENTS¶

MACD consists of three values calculated from closing price:

Component	Calculation	Purpose
MACD Line	12-period EMA − 26-period EMA	Measures spread between two EMAs
Signal Line	9-period EMA of the MACD Line	Smoothed trigger for crossover signals
Histogram	MACD Line − Signal Line	Visualises momentum expansion or contraction

Standard default parameters: 12 / 26 / 9 — calibrated for daily equity charts.

Tip

For intraday timeframes, the default 12/26/9 settings will produce excessive lag. Common intraday alternatives are 5/13/4 or 8/17/9. Adjust parameters in the indicator settings panel.

HOW TO USE¶

Reading the Histogram¶

A positive histogram means the MACD line is above the signal line. A growing histogram means momentum is accelerating in the current direction.

Example — SPY at $525:

12-period EMA: $523.10
26-period EMA: $518.40
MACD Line: $523.10 − $518.40 = $4.70
Signal Line (9-period EMA of MACD): $4.20
Histogram: $4.70 − $4.20 = +$0.50

If the prior bar was +$0.30 and the current bar is +$0.50, momentum is expanding and confirms the uptrend.

Signal Types¶

Signal	Condition	Interpretation
Bullish crossover	MACD line crosses above signal line	Potential long entry signal
Bearish crossover	MACD line crosses below signal line	Potential short entry signal
Zero-line crossover (bullish)	MACD line crosses above zero	EMA crossover confirmed in price; trend is bullish
Zero-line crossover (bearish)	MACD line crosses below zero	EMA crossover confirmed in price; trend is bearish
Histogram divergence	Price makes new swing low; histogram bars shrink	Loss of downside momentum; potential reversal ahead of price confirmation

Tip

Use the zero-line as a directional filter. Only act on bullish MACD crossovers when the MACD line is already above zero. Only act on bearish crossovers when it is below zero. This reduces false signals in trending markets.

Common Use Cases¶

Swing trading entries and exits — crossover signals provide a defined, rules-based trigger in place of subjective price reads.
Trend confirmation — zero-line position tells you whether the broader price trend is bullish or bearish before committing to a trade.
Divergence setups — histogram divergence is the highest-conviction MACD signal, warning of reversals before price confirms them.

LIMITATIONS¶

Limitation	Detail
Lagging	Signals arrive after a significant portion of the move has already occurred
Whipsaws	In choppy, sideways markets, MACD produces repeated false crossovers resulting in a string of small losses
No overbought/oversold levels	MACD has no fixed upper or lower bound; unlike RSI, extreme readings cannot be defined or compared across instruments
Default settings	The 12/26/9 defaults were tuned for 1970s daily equity data and require adjustment for modern intraday use