Relative Strength Index (RSI)

5 important roles of Relative Strength Index (RSI)

by Ankit Jaiswal on Indicators & Oscillators, Technical Analysis
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Relative Strength Index (RSI) is a momentum oscillator, developed by J. Welles Wilder, which measures the speed and velocity of price movement of trading instruments (stocks, commodity futures, bonds, forex etc.) over a specified period of time.

The objective of RSI indicator is to measure the change in price momentum.

It is a leading indicator and is widely used by Technical Analysts over the globe.

RSI can be used to spot a general trend.

It is considered overbought when it goes above 70 and oversold when it goes below 30

 Moreover, RSI can also be used to look for failure swings, divergences and center line crossover.


The formula for calculating Relative Strength Index is as follows

RSI = 100 – 100 / (1 + RS)
RS  =  Average Gain over specified period/ Average loss over the same period

Also ReadCANSLIM- the winning Techno-Fundamental strategy

The default setting for Relative Strength Index is 14, but you may change this value to decrease or increase sensitivity based on your requirement.

For instance, 12-day RSI is more likely to reach overbought or oversold levels than 24-day RSI.

You can watch the video below to know more about the calculation and concept of RSI:

Apart from reading overbought and oversold condition, there are certain special features in RSI. Those are as follows-

1. Trendline application

It is an interesting fact that RSI and the closing chart almost go hand in hand.

Sometimes it becomes difficult to differentiate which one is RSI and which one is the closing chart.

We apply trend lines in the closing chart may it be up or down.

Similarly, we can apply closing trend lines in the same manner in RSI.

It is interesting to know that RSI trend lines would be broken at least 3-4 days before and this gives an advanced signal that price is going to break the same trend line within a day or two.

Also ReadA complete overview of trend and theory of retracement

LIC Housing trendline breakout

The above is the chart of LIC Housing Finance and as we can see that RSI already gave an advanced sell signal.

The first sell signal came on 9th May 2017 when RSI breaches the uptrend line and the second sell signal came in on 14th June 2017, when the RSI bounced after breaching the uptrend line and faces a strong resistance from the uptrend line in RSI as shown in the chart.

Soon after the second sell signal came in, the stock corrected about 25% from its high.

2. Pattern breakout

We know that formation of pattern is an interesting phenomenon in building of the chart. Any pattern may it be reversal or continuation will stage a breakout at a particular point of time.

It is again interesting to know as RSI considers the underlying relative strength of a stock over a specified period of time. Such breakout will occur at least 2-3 days in advance in RSI which price will follow in due course.

H and S pattern RSI FCEL

The above is the chart of Future consumer where there was a head and shoulder pattern was there in RSI. At the same time, there was a double top formation at the top and M-top formation in Bollinger which rather confirmed our sell signal. Soon after the RSI line breached the neckline, there was a good correction in the price.

If you want to become an expert in techncial analysis you may do: NSE Academy Certified Technical Analysis course.

3. Advance breakout and breakdown

The concept of advance breakout and breakdown works wonderfully in OBV indicator.

The same logic is true also in case of RSI.

Advance breakout implies when the indicator (RSI here) has breached the previous top while the price hasn’t breached the previous top yet.

So it’s basically an advanced or early signal which indicates that price will also follow the indicator in the coming few sessions.

The below is the chart of Sanghvi movers, as we closely watch the RSI line, we can see that RSI already breached the previous resistance but the price still hovering below the previous resistance.

Soon after the price breakout, the stock witnessed a good rally.

Advanced breakout sanghvi movers

Similarly, in case of advanced breakdown, the indicator has breached the previous bottom but the price is still below or at the previous bottom, thus giving an early signal that the price may soon break the previous bottom and see some correction in the coming days.

The below is the price chart of Asian paints where we can clearly see that RSI breached its previous support quite before. Soon after the price also followed the same and witnessed a strong correction almost from its highs.

Advanced breakdown asian paints

4. Role of 50

In RSI, the mid 50 line acts as a very important line to indicate the price direction.

It is usually seen that the price continue to stay above the mid 50 line during the bullish phase while it faces strong resistance from the 50 line in RSI during the bearish phase of the market.

However, there may be a lot of whipsaws in the daily chart, so it’s better to look at the bigger timeframe chart say weekly chart.

Role of 50 RSI Tata motors

The above is the chart of Tata Motors and we can see that whenever the RSI is maintaining above the mid 50 line, the stock was in the bullish mode while when the price was below the mid 50 line, the stock showed good correction.

In short, we can say that the mid 50 line in RSI acts as a good trend changer.

5. Failure swing

A bullish failure swing forms when RSI moves below 30 (oversold), bounces above 30, pulls back, holds above 30 and then breaks its prior high.

It is basically a move to oversold levels and then a higher low above oversold levels.

The below is the chart of Asian Paints where there is a clear failure swing in RSI. Soon after the resistance got broke in RSI, the stock witnessed a good rally.

Failure swing

A bearish failure swing forms when RSI moves above 70, pulls back, bounces, fails to exceed 70 and then breaks its prior low.

It is basically a move to overbought levels and then a lower high below overbought levels.

The below is the chart of SBI where there is a clear failure swing in RSI.

Soon after the support was broken in RSI, the stock saw a good correction within a month’s time.

Also ReadRSI Failure Swings: Trading the RSI the Wilder Way!

Failure swing


Just like other indicators, the signal quality will also depend upon the characteristics of the underlying security.

RSI should also be used in conjunction with other indicators and technical parameters to generate better and more confirmed trading signals.

Moreover, those traders who are unable to devote much time in analysing charts of various securities may benefit from scan section in  StockEdge mobile app.

To know how to use the scan section of StockEdge Mobile App effectively you can watch the video below:

It provides an easier way to track certain trade various opportunities based on RSI indicator.

The app also provides an opportunity to club RSI strategy with other indicators, volume, and price patterns base strategies on EOD basis to develop more confirmed signals.

Feel free to give us your feedback by writing in the comment box below.

Keep Learning!!


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Disclaimer wants to remind you that all our content is created solely for the purpose of education. No strategy, stock, commodity, fund or any other security discussed here is any way a recommendation for trading or investing. will not be any way responsible for trading losses incurred by any individual or entity for trading with real money. Please take advise of certified financial advisers before trading or investing.


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