MACD components
A common configuration uses a 12-period EMA and 26-period EMA. The MACD line is the faster EMA minus the slower EMA.
A 9-period EMA of the MACD line is commonly used as the signal line. The histogram represents the difference between the MACD line and signal line.
The zero line
MACD above zero means the faster EMA is above the slower EMA. MACD below zero means the faster EMA is below the slower EMA.
MACD and signal-line crossovers
A MACD cross above its signal line indicates the faster-changing MACD line has moved above its own smoothed signal line. A cross below indicates the opposite.
Crossovers are descriptive events, not guarantees of future direction.
Reading the histogram
The histogram expands as the distance between MACD and its signal line grows and contracts as the lines converge.
This can help visualize changes in momentum, but histogram contraction does not by itself prove price is about to reverse.
Common MACD mistakes
Trading every crossover
Sideways markets can produce repeated whipsaws.
Ignoring timeframe
A MACD state on 15 minutes can differ materially from the 4-hour state.
Treating lag as a flaw that can disappear
MACD is built from moving averages of historical prices, so some lag is inherent.
Key takeaways
- MACD commonly uses the difference between 12- and 26-period EMAs.
- The signal line is commonly a 9-period EMA of MACD.
- The histogram visualizes the distance between MACD and its signal line.
- Crossovers require market context because sideways conditions can create whipsaws.
Sources & further reading
This lesson is educational material. Market structure, exchange rules, fees, margin requirements and derivatives mechanics can differ by venue and can change over time. Verify current rules with the venue you use.