RSI (Relative Strength Index) is a momentum oscillator running from 0 to 100. Above 70 = overbought (may be due for a pullback). Below 30 = oversold (may bounce). It is calculated over 14 periods by default.
The calculation compares average gains to average losses over the lookback period. A stock that closes higher every day for 14 days would have an RSI near 100. A stock that closes lower every day would have an RSI near 0.
One of the most useful RSI signals is divergence: when price makes a new high but RSI makes a lower high, the uptrend may be weakening. On StockifyX, RSI is displayed as a badge on every stock chart, color-coded green (oversold), red (overbought), or yellow (neutral).
RSI works best in ranging markets. In strong trending markets, RSI can stay overbought for extended periods. Always combine RSI with price action and volume for confirmation.