Relative Strength Index (RSI)

The Relative Strength Index is a momentum oscillator, plotted on a 0–100 scale, that measures the speed and size of recent price changes to gauge whether an instrument is overbought (typically above 70) or oversold (typically below 30). Traders use it both to spot potential reversal points and to confirm the strength of an existing trend. RSI can stay in "overbought" or "oversold" territory for extended periods during a strong trend, so many traders treat extreme readings as a caution flag rather than an automatic reversal signal on their own.