The Choppiness Index (CHOP) is a technical analysis indicator used to determine if a market is trending or trading sideways (no defined trend).

This indicator does not show the direction of the trend, but rather the level of "churn" or "choppiness" of the market.

The index has a range of values between 0 and 100. Values close to 100 indicate that the market is trading sideways (range). Values close to 0 suggest that the market is in a strong trend (either bullish or bearish).

A high Choppiness Index suggests that the market is "choppy", meaning there is no clear direction and prices are fluctuating within a range. A low Choppiness Index indicates that the market is in a strong trend, with a clear directional movement.

It was developed by trader E.W. Dreiss.