Average Directional Index (ADX): formula and how to read it

How strong the current trend is, whichever way it points. Wilder's ADX smooths the gap between upward and downward price movement over 14 days, from 0 to 100. It measures the strength of a trend, not its direction: above 25 is generally read as a trending market and below 20 as a drifting or sideways one.

Stock Meadow groups it under Price trend, and shows it in tables as ADX 14.

ADX = Wilder's 14-day average of DX; DX = 100 × |+DI − −DI| ÷ (+DI + −DI), where +DI and −DI measure the size of upward and downward moves relative to the true range

If +DI is 30 and −DI is 10, DX is 100 × 20 ÷ 40 = 50. An ADX near 50 means a very strong trend. The numbers are made up for illustration.

It runs from 0 to 100. Above 25 is generally read as a trending market and below 20 as a drifting, sideways one. It is a filter only, because it has no better end: combine it with a direction measure such as price vs. the 50-day EMA.

It can be used as a filter and as a column, but not for scoring: it describes a company rather than making it better or worse.

• It tells you the trend is strong, not whether it is up or down.
• It is slow: the 14-day smoothing means it keeps rising for a while after a trend has peaked.
• Needs about 28 trading days of prices.

How Stock Meadow handles gaps. Usually blank when there are fewer than 28 days of prices.

Treat any single metric as one clue, and read the company's financial statements before drawing a conclusion. Stock Meadow's figures are research tools based on reported data, not investment advice.

No scoring model uses it. It is a filter and a table column only.

Read about every scoring model in How scores work.

• Price vs. 50-Day EMA: how far the price sits above its recent trend line.
• MACD Histogram: whether short-term momentum is building or fading, relative to the price.
• Parabolic SAR Trend: 1 when the Parabolic SAR sits below the price (up-trend), -1 when above (down-trend).

What is a good ADX value?

There is no good or bad value. Above 25 means a strong trend in either direction and below 20 a weak or absent one.

Can I score stocks on ADX 14?

It can be used as a filter and as a column, but not for scoring: it describes a company rather than making it better or worse.

Why is ADX 14 blank for some stocks?

It is usually blank when there are fewer than 28 days of prices. Stock Meadow leaves the figure blank rather than guessing it.