MACD day trading seems simple enough. Just buy long when the MACD is at the bottom of the chart and sell when the MACD is at the top. Or, you trade the crossover patterns. Unfortunately, it's not that easy.
The MACD is an important day trading tool, but it has its limitations. MACD (Moving Average Convergence Divergence) is a trailing indicator. This means that it computes a series of previous stock prices, creates two sets of average prices based on this formula, and draws two lines to indicate their trends. Most MACD day trading tools will also show a histogram, which is a series of bars standing either below or above the signal line.
The great thing about the MACD indicator is that it gives a clear visual day trading tool. It is probably one of the first technical indicators that many day traders find and begin using. It seems to predict price movement - but, it does not. The new day trader must remember this important fact: it is a trailing indicator, not a predictor of price movement. This is a critical distinction.
MACD day trading has its limitations. For example, when a stock gaps down by a large amount, the MACD lines plummet with it. But, if you will watch your charts, you'll also see that the MACD lines will show a crossover pattern (thought by many to be a "buy" signal), even though the stock is trading sideways or even going down in price. The reason this happens is due to the trailing mathematical formula in the MACD.
The chart below shows an example of this:
On the above 5-minute chart, SIG shows a "gap down" on the morning of 01.11.2017. The green box of price shows that that the stock showed some short covering after the gap down and price moved up. But the red box that highlights the MACD indicator still shows a bearish divergence. So, if you were trading this stock solely based on the MACD indicator, then you would never have taken this trade.
In my books, I talk at more length about using the MACD in trading stocks. One point deserves repeating though. When I am looking at gap down stocks, I use the MACD as one of several technical indicators. I wait for the MACD to form a "confirmed bottom" before buying the stock. A confirmed bottom is what happens when the fast line of the MACD forms a horizontal line, just before it hooks upwards. The important point is that this confirmed bottom may appear at one point on a 5-minute chart, and it may appear later on a 10-minute chart. Using the 5-minute chart on a gap down stock can create a premature entry if that is the only indicator you're using. It may show a bottom and yet continue to fall in price. That is why this indicator must be combined with other indicators for good trading.
So, the MACD is not a fool-proof technical indicator. But, it can be one of your important indicators. Used in conjunction with other indicators, such as RSI (Relative Strength Index), it can be a powerful day trading tool.
The main purpose of this article is just to alert you to the fact that using the MACD in day trading is not a stand-alone indicator. So, don't trust it as a Holy Grail that will waltz you toward easy profits.
Your day trading platform will come with a default setting for the MACD. You can experiment with various settings. But, if you are day trading, rather than doing long term investing, a tighter MACD setting might be more useful to you.
If you'd like to read more about the MACD, then the Chart School is a good resource. Click here to read one of their articles about trading with the MACD.