Relative strength is a ratio of a stock price performance to a market average (index) performance. It is used in technical analysis.
It is not to be confused with relative strength index.
To calculate the relative strength of a particular stock, divide the percentage change over some time period by the percentage change of a particular index over the same time period.
Relative Rotation Graphs (RRG) show the relative strength and momentum of mood swings in the market compared to benchmarks. The "JdK RS-Ratio" (relative strength, RS) was developed by Julius de Kempenaer, a sellside analyst in The Netherlands.
Relative strength compares the performance of one security, sector, or market with another, usually by dividing the price of the first by the price of a benchmark or comparison asset. This produces a ratio line that rises when the first asset is outperforming the comparison asset and falls when it is underperforming.
The relative strength index is a different technical indicator. It is a momentum oscillator that measures the speed and magnitude of recent price movements of a single security, rather than comparing that security directly with a benchmark. The two terms are therefore related in name but measure different concepts in technical analysis.