NR7 is a chart pattern based on traditional candlesticks.  NR7 means that the last candlestick has the narrowest price range of the last 7 candlesticks.

A description of “NR7-2” means that the stock chart shows an NR7 pattern for the last candlestick, and for the previous candlestick.  “NR7-3”, “NR7-4”, etc., are all defined in the same way.  This information is also available as a filter.

The NR7 pattern shows when a stock’s price shows a short-term pattern of decreasing volatility.  In this way NR7 is like a triangle chart pattern, but with more emphasis on the volatility, and less emphasis on the specific shape or direction.  In either case the common assumption is that volatility is like a spring.  When you push in on it, it has to pop back out.  The longer and harder you push, the more explosive the final reaction will be.

The NR7 pattern does not, by itself, predict which direction a stock will move.  People use it to predict which stocks are likely to make a large price move.