What is the use of ADX in trading and why it is important ?

The ADX quantifies trend strength by measuring directional movement over a given time frame. It provides traders with specific numbers (from 0 to 100) that represent strong or weak price trends. Traders can simply refer to the numbers to quickly assess the strength of a trend.

The ADX identifies a strong trend when the ADX is over 25 and a weak trend when the ADX is below 20. Crossovers of the -DI and +DI lines can be used to generate trade signals. For example, if the +DI line crosses above the -DI line and the ADX is above 20, or ideally above 25, then that is a potential signal to buy.

The ADX Indicator actually works best when combined with other technical indicators. One of the best combinations is with the Relative Strength Index, or RSI. Because the ADX measures the intensity of the trend the RSI can help with entries and exits by giving a time based component to the trend