Calculating Stochastic RSI and Reconciling Its Output Conventions

Summary

The post explains Stochastic RSI as an RSI series normalized against its recent range, then smoothed to produce a fast line and a signal line. It relates common naming conventions: the fast %K line corresponds to the Stochastic RSI output, while %D corresponds to a moving average of that line. The author describes an implementation built from RSI, rolling lows and highs, moving averages, and a final scaling step.

The motivation is disagreement between indicator descriptions and charting platforms. The author says a library call with parameters 14, 14, 3, 3 did not match other platforms, then reports that interpreting the parameters through the formula and comparing calculated values produced a closer match. This is an empirical comparison, not a formal validation. The article also notes that multiple forms of the indicator exist, and it does not fully document all variants or settle platform-specific initialization and edge-case behavior. Results may therefore differ with parameter order, smoothing choices, and implementation details.

Key ideas

• Stochastic RSI applies a stochastic range calculation to RSI rather than directly to price.
• The calculation can produce a fast %K line and a smoothed %D signal line.
• Different platforms may assign parameters and output names differently.
• The author compares a custom calculation with charting outputs to infer a matching parameter interpretation.
• The post does not establish one universal implementation or resolve every platform variation.

Tags

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.