Ratio of average up-closes to average down-closes over N bars, normalised 0–100. > 70 = overbought, < 30 = oversold.
RS = avg gain / avg loss over N periods RSI = 100 − 100/(1 + RS)
Overbought/oversold reversals, divergence with price (price makes lower low, RSI makes higher low = bullish divergence), 50-level as trend filter.
RSI can stay pinned in extreme zones for weeks in strong trends — "overbought" isn't "sell". Divergence often precedes reversal but timing is unreliable.
Nifty 50 daily bars with RSI (Relative Strength Index) pre-loaded:
8 strategies use RSI (Relative Strength Index):