The RSI (Relative Strength Index) indicator is one of the most popular oscillators in trading, measuring the speed and magnitude of price change over a chosen period. In binary options, RSI is most often used to find zones where the current price move looks excessive and the odds of a correction or reversal rise.
How RSI is calculated
RSI is calculated from the ratio of average price gains to average price losses over a chosen period and is displayed on a scale from 0 to 100. A value closer to 100 indicates dominant price gains over the calculation period; a value closer to 0 indicates dominant declines. The standard calculation period is 14, but it can be adjusted depending on the timeframe and chosen strategy.
Overbought and oversold zones
The classic interpretation of RSI relies on two threshold levels:
- Overbought zone (usually above 70) — price has risen so intensely that the odds of a correction or downward reversal increase.
- Oversold zone (usually below 30) — price has fallen so intensely that the odds of a correction or upward reversal increase.
On more volatile assets, these thresholds are sometimes shifted to 80 and 20 to cut down on false signals from brief spikes.
How to use RSI for signals in binary options
The simplest approach is to open a buy trade when RSI exits the oversold zone back above the threshold, and a sell trade when it exits the overbought zone. It's important to wait for the exit from the zone, not the entry into it: entering an overbought zone doesn't mean an immediate reversal — price can stay there for a while during a strong trend.
RSI divergence
Besides overbought and oversold zones, RSI is often used to find divergence — a situation where price sets a new high or low but the indicator doesn't confirm that move. A detailed look at divergence and its types is in the article on the indicator divergence strategy.
Tuning the RSI period for a timeframe
The standard 14-period setting suits most situations, but on short binary options timeframes a shortened period (5–9) is sometimes used for a faster indicator reaction to price changes. A shorter period increases the number of signals while also raising the odds of false triggers from random noise.
Limitations of RSI
RSI performs poorly during a strong directional trend: the indicator can stay in an overbought or oversold zone for a long time with no reversal, leading to a string of losses for traders who blindly follow the classic interpretation. For that reason, RSI is best combined with identifying the overall trend before trading off overbought and oversold levels.
Combining RSI with other indicators
To improve reliability, RSI is often paired with trend indicators — moving averages or ADX — to tell a reversal apart from a continuation of a strong move. This combination is covered in detail in the article on combining indicators without conflicts.
Automating RSI calculation
Calculating RSI values, overbought/oversold zones, and divergence can be fully automated. A trading robot for Pocket Option calculates these parameters in real time and generates a signal only when set conditions are met — details on the features page.
Conclusion
The RSI indicator is a convenient tool for spotting zones of excessive price movement, but it requires accounting for the overall trend and additional filters. Use the exit from overbought and oversold zones rather than the entry into them, and watch for divergence to catch reversals early. Automatic calculation is available in the robot's plans.