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Technical Analysis

What Is RSI?

Definition and plain-English explanation of "RSI"

RSI — Technical Analysis illustration

The Relative Strength Index (RSI) is a momentum indicator that measures the speed and magnitude of price changes on a scale of 0–100. An RSI above 70 suggests a stock may be overbought (potentially due for a pullback). An RSI below 30 suggests it may be oversold (potentially a buying opportunity). RSI was developed by J. Welles Wilder in 1978.

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