GlossaryIntermediate
Average Directional Index (ADX)
A 0-100 indicator that measures trend strength specifically, independent of whether the trend is up or down.
The Average Directional Index (ADX), developed by J. Welles Wilder, measures trend strength on a 0-100 scale, deliberately independent of trend direction — a rising ADX means the current trend (whichever direction it's in) is strengthening, not that price is necessarily rising.
ADX is derived from two companion lines, +DI and -DI (positive and negative directional indicators), which separately track upward and downward directional movement; ADX itself summarizes their relationship into a single strength reading. See Kaavon's dedicated ADX article for the full calculation.
Examples
- A rising ADX during a downtrend indicates the downtrend is strengthening, not that a reversal to the upside is near.
- ADX is commonly used alongside a directional indicator like a moving average, since ADX alone says nothing about which direction the trend is actually moving.