How to use the stochastic oscillator

The stochastic oscillator is a momentum indicator that compares a security's closing price with its price range over a set period, typically 14 periods. By showing the position of the closing price relative to recent highs and lows, it helps traders assess market momentum and identify potential trend reversals.

Displayed on a scale of 0 to 100, the indicator highlights potential overbought and oversold conditions. Its responsiveness can be adjusted by changing the time period or applying a moving average to smooth price fluctuations.

Developed by George Lane in the 1950s, the stochastic oscillator consists of two lines: %K, which represents the current value, and %D, a three-period moving average of %K. Traders monitor the relationship between these lines to help spot possible changes in market direction and trading opportunities.

Here are some of the key points to remember about the stochastic oscillator:

• It provides trading signals by identifying overbought and oversold conditions. When the reading is above 80, it indicates potential overbought levels, and readings below 20 indicate potential oversold levels.
• In essence, it measures the current price relative to its price range over a given period. The percentage calculated indicates where the current closing price sits within the selected price range and can help assess momentum.
• It's celebrated for its simplicity and ease of integration into various trading strategies, and some strategies are built with the oscillator at their core.
• It allows traders to pinpoint potential entry and exit points - especially in forex and stock trading - with greater accuracy.
• Despite its usefulness, the stochastic oscillator can produce false signals, particularly in volatile markets, so it's often used with trend analysis for confirmation.

Since the stochastic oscillator is a momentum indicator, it's important to understand what momentum actually means.

In short, momentum refers to how quickly the price of a financial asset, such as a stock or bond, is rising or falling. It's best to think of it like a car accelerating: the faster the car (or price) moves, the more momentum it has.

Understanding trend reversals

Trend reversals occur when an asset's price changes direction, signalling a potential shift from an upward trend to a downward trend, or vice versa. For traders, identifying these turning points is important as they can create opportunities to enter or exit positions at favourable times.

Recognising a trend reversal can help traders adapt their strategies to changing market conditions. A new bullish trend may present buying opportunities, while a bearish reversal could signal the need to sell or manage risk more carefully. Because trend reversals often mark the start of a new market phase, spotting them early can be valuable. But what does this mean for the oscillator?

The stochastic oscillator helps traders spot when the market might change direction and confirm when prices act unusually (a potential trend reversal).

By tracking the relationship between %K and %D, traders can assess market momentum and identify any trend changes. Crossovers between these two lines are often used to signal possible buying or selling opportunities, while readings at extreme levels may indicate overbought or oversold conditions.

Most trading platforms can calculate the stochastic oscillator indicator for you, but it's still important for traders to understand how it works. You can use the following calculation to harness the stochastic oscillator indicator:

%K = {(C – L14) / (H14 – L14)} x 100

Below is a quick breakdown of the symbols used:

• C = Latest closing price
• L14 = Lowest low over the period in question
• H14 = Highest high over the period

Once %K is calculated, it's plotted as a line on a section below the chart. This is also sometimes referred to as the 'fast stochastic' indicator. It is generally accepted that in a market trending upward, prices will close near the high, and in a market trending downward, prices will close near the low.

There will often be two lines on the chart. The second line is known as the %D line, which is a moving average of the %K line. This %D line is a 3-period simple moving average of %K, and it's known as the 'slow stochastic' indicator because it responds more slowly to market price changes compared to %K.

If you're looking to use the indicator, we have come up with some stochastic oscillator strategies you can implement in your own trading.

Stochastic overbought/oversold strategy

In this stochastic trading strategy, traders use the oscillator to identify trade exit and entry points.

As a rule, traders look to place a buy trade when an instrument is oversold. This signal is given when the stochastic indicator has been below 20 and then rises above 20. Conversely, traders look to place a sell trade when an instrument is overbought. This signal is given when the stochastic indicator has been above 80 and then falls below 80.

It's important to remember that overbought and oversold indicators can be misleading. An instrument will not necessarily fall in price just because it is overbought. The indicator is simply showing that the price is trading near the top or the bottom of the range - these conditions can last for a while.

Example: Suppose a FTSE 100-listed retailer's stochastic oscillator has been trading below 20 for several sessions, indicating oversold conditions, before rising back above the 20 level. Some traders might view this as a potential signal to consider a long position, particularly if it aligns with broader trend analysis. Figures used here are hypothetical and for illustrative purposes only, and this does not constitute financial advice or a recommendation to trade.

Stochastic divergence strategy

Another popular approach is the divergence strategy, where traders compare price action against the stochastic oscillator's readings. With this strategy, traders look to see if an instrument's price is making new highs or lows, even if the stochastic indicator isn't showing that. This can signal that the trend is about to reverse.

A bullish divergence forms when an asset's price records a lower low, while the stochastic oscillator creates a higher low. This suggests that downward momentum is weakening, even though the price continues to fall, potentially signalling an upcoming move higher.

A bearish divergence occurs when an asset's price reaches a higher high, but the stochastic oscillator forms a lower high. This indicates that buying momentum is fading and could be an early warning of a potential downward reversal.

However, divergence alone should not be treated as a trading signal. Prices can continue trending in the same direction for an extended period despite divergence appearing on the indicator. For this reason, traders typically wait for confirmation from price action, such as a clear reversal pattern or a break in trend, before entering a trade. This additional confirmation can help reduce the risk of acting on false signals.

Example: For example, imagine a FTSE 100 index constituent records a new low in price, while the stochastic oscillator forms a higher low over the same period. This bullish divergence might suggest that downward momentum is fading, although traders would typically look for further confirmation before acting. As with all examples in this guide, figures are hypothetical and used for illustrative purposes only.

Stochastic crossover

Another popular strategy, stochastic crossover occurs when the two lines on the oscillator cross in an overbought or oversold region.

When the %K line rises above the %D line while the stochastic oscillator is in the oversold zone, it is often viewed as a bullish signal, suggesting that upward momentum may be building. Conversely, when the %K line falls below the %D line in the overbought zone, it is considered a bearish signal, indicating that downward momentum could be emerging.

These crossover signals are generally more effective in range-bound markets, where prices move within established support and resistance levels. In strongly trending markets, however, the stochastic oscillator can remain in overbought or oversold territory for extended periods, making signals less reliable.

The relative strength index (RSI) and the stochastic indicator are both price momentum oscillators used in technical analysis. They are often used in tandem, but they have very different underlying theories and methods.

The stochastic oscillator is predicated on the assumption that closing prices should move in the same direction as the current trend.

On the other hand, the RSI tracks overbought and oversold levels by measuring the velocity of price movements. In short, the RSI was designed to measure the speed of price movements, while the stochastic oscillator measures the closing price's position within its recent range.

Here are some of the advantages and disadvantages of using the stochastic oscillator:

Advantages of the stochastic oscillator

• Distinct entry and exit signals: The oscillator signals when it reaches overbought or oversold levels, helping traders identify potential entry and exit points.
• Overbought/oversold identification: The oscillator works on a scale of 0 to 100 as it is a bounded oscillator. This simplifies the process of spotting overbought and oversold conditions.

When momentum and price action confirm a stochastic signal in the same direction, it increases the reliability of the trade setup. This is why the stochastic oscillator is most effective when used alongside other technical indicators, as well as price action signals and chart patterns, to provide additional confirmation before entering or exiting a trade.

Disadvantages of the stochastic oscillator

• Volatility and inconsistent range: The oscillator's percentage moves don't always scale consistently with the size of the underlying price move. A rise from 20 to 80 might reflect a sharp price increase, while a fall from 80 back to 20 could reflect a much smaller one, making the readings harder to interpret at face value.
• Additional confirmation is usually needed: It's common for traders to pair stochastic oscillators with other indicators or patterns to validate the price movements. Relying solely on stochastic readings can be risky, and more information is usually needed for a successful trade.

Technical analysis is a valuable tool for understanding price movements and momentum, and stochastic oscillators are no exception, as they can give you a better idea of price movements and momentum.

If you're ready to begin your trading journey, or if you're looking for a reliable trading platform that offers a wide range of markets and financial instruments, then sign up or create a demo account with Trade Nation today.

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