The Relative Strength Index (RSI) is a momentum indicator used in technical analysis that measures the speed and magnitude of recent price changes to evaluate whether an asset is overbought or oversold. RSI is displayed as a number between 0 and 100. A reading above 70 generally suggests the asset may be overbought (and due for a correction), while a reading below 30 suggests it may be oversold (and potentially undervalued). RSI is one of the most widely used indicators among crypto traders.