When Is Price Stretched? The Stochastic Oscillator
The Stochastic Oscillator measures where current price sits relative to its recent high-low range. Use it to spot momentum shifts and time entries when price pulls back in a trend.
Stochastics show whether price is near the top or bottom of its recent range. Values above 80 = overbought (near recent highs). Below 20 = oversold (near recent lows). Watch for %K crossing above %D in oversold territory (bullish) or %K crossing below %D in overbought territory (bearish). Best used to time pullback entries in trending markets, NOT as a standalone reversal signal.
What is the Stochastic Oscillator?
The Stochastic Oscillator compares the current closing price to the price range over a lookback period (typically 14 periods). It consists of two lines:
- %K line (fast) — the main oscillator value, showing current momentum
- %D line (slow) — a 3-period moving average of %K, acting as a signal line
Both lines oscillate between 0 and 100. Readings above 80 suggest overbought conditions (price near recent highs). Readings below 20 suggest oversold conditions (price near recent lows).
How do you read stochastic signals?
Stochastics generate three types of signals:
1. Crossover signals
Bullish: %K crosses above %D while both are below 20 (oversold) → momentum shifting up from a pullback
Bearish: %K crosses below %D while both are above 80 (overbought) → momentum weakening after a rally
2. Overbought/oversold zones
Above 80 = price near recent highs (caution for longs, watch for reversal)
Below 20 = price near recent lows (watch for bounce in uptrends, continuation risk in downtrends)
3. Divergences
Bullish divergence: Price makes lower lows, but stochastics make higher lows → weakening downward momentum
Bearish divergence: Price makes higher highs, but stochastics make lower highs → weakening upward momentum
When should you use stochastics?
Stochastics work best in range-bound or choppy markets where price oscillates between support and resistance. They help you:
- Time pullback entries — buy when stochastics cross up from oversold in an uptrend
- Spot exhaustion — exit longs when stochastics cross down from overbought
- Confirm divergences — combine with price action to spot potential reversals
What are common stochastic settings?
The standard Stochastic Oscillator uses:
- %K period: 14 — lookback period for the high-low range
- %K slowing: 3 — smooths the %K line to reduce whipsaws
- %D period: 3 — moving average of %K
Fast Stochastic uses raw %K with no smoothing (more sensitive, more false signals).
Slow Stochastic applies smoothing to %K (the default 14,3,3 setting — this is what most traders use).
Stochastic zones and what they mean
Test Stochastics on Any Stock
Use the MadStocks Stochastic Analyzer to see live %K/%D readings and crossovers on any ticker.