Home/Glossary/Stochastic oscillator
Home/Glossary/Stochastic oscillator
Technical analysis

Stochastic oscillator

By Jarosław Wasiński • Published: • Updated:
An oscillator locating Close within the highest-High/lowest-Low range of a specified window. Raw %K uses a zero-to-100 scale; fast, slow and full versions differ in %K and %D smoothing. The 80/20 thresholds are conventions, not reversal instructions. Data, parameters and close availability affect readings.
Example. The window’s highest High is 1.1100, lowest Low 1.1000 and current Close 1.1080. Raw %K = 100 × (1.1080 − 1.1000)/(1.1100 − 1.1000) = 80. Averaging successive raw values of 60, 70 and 80 gives 70, which is a smoothed series rather than the latest raw reading.

Raw and smoothed lines

Raw stochastic locates Close within the range of n bars. Fast %K is commonly raw, with %D its average. In slow or full variants, %K can also be smoothed and %D smooths that resulting series. A 14/3/3 configuration needs the role of every number and averaging method specified.

Bounds and special cases

With Close inside the chosen range, the reading lies between zero and 100. Equal window High and Low produce a zero denominator, requiring a documented software convention. The window commonly includes the current bar, so unfinished data changes the value. Stochastic RSI applies a related transformation to RSI rather than directly to price.

Threshold interpretation

Eighty and 20 are popular conventions. Price can remain near a range boundary in a trend; an extreme reading does not mandate a counter-trend position. Relative speed versus RSI depends on both parameter sets rather than being constant. Crossovers and threshold re-entry need evaluation as complete rules, including costs.

Source of the definition

TradingView: stochastic calculation. Documentation of the construction or concept is not a guarantee of strategy results.

FAQ

Is %K always raw?
No. Slow and full variants can smooth it; check the implementation.
Are stochastic and Stochastic RSI identical?
No. The former compares prices; the latter locates RSI within its own range.

← Back to the full glossary

Jarosław Wasiński

Editor-in-chief, ForexMechanics.com • Macro & FX analyst

Independent analyst and practitioner with over 20 years of experience in financial markets. Actively involved in Forex since 2007, with a focus on fundamental analysis, OTC market structure, and disciplined capital risk management.

  • Creator and editor-in-chief of MyBank.pl, providing reliable financial education since 2004.
  • Author of hundreds of in-depth market commentaries, structural analyses, and educational materials for traders and investors.
  • Advocate for market transparency, promoting education grounded in hard data and institutional reports (BIS, ESMA, CFTC).

All content is educational and informational only – it does not constitute investment advice or a recommendation. Remember: leveraged trading (Forex/CFD) carries a high risk of rapid capital loss.