How one-sided the last fourteen days of price action have been, on a 0 to 100 scale. Above 70 is historically overbought; below 30, oversold - the classic momentum gauge.
RSI measures how one-sided the last 14 days of price moves have been, on a 0-100 scale. When buying dominates it climbs toward 100; when selling dominates it falls toward 0. The edges are where it earns its keep - in the middle, the direction of travel matters more than the level.
Selling has been relentless and is statistically stretched. Historically where capitulation lows and sharp relief rallies have started.
The normal range, no extreme. Watch the 50 line: rising through it supports an uptrend, falling through it warns momentum is fading.
Gains have far outpaced losses. Historically a zone where rallies stall, chop or retrace - common near local tops.
A short-term momentum gauge - it swings within days, not months. Use it to spot stretched conditions, not as a standalone buy or sell signal: strong trends can stay overbought or oversold for a while.
A momentum oscillator developed by J. Welles Wilder in 1978. It compares the size of recent gains to the size of recent losses over a lookback window (we use the standard 14 days) and compresses the result onto a 0 to 100 scale. High readings mean the advance has been one-sided; low readings mean the decline has been one-sided.
Each day's move is split into gain or loss. Both are smoothed with Wilder's method (a slow-moving average that weights history), giving average gain and average loss. Relative strength is RS = average gain ÷ average loss, and RSI = 100 − 100 ÷ (1 + RS). We compute it on this page from daily closes - nothing is pre-baked.
They are Wilder's original thresholds and remain the convention. Above 70, fourteen-day gains have outweighed losses by more than two to one - historically a stretched market. Below 30, the reverse. In strong trends RSI can sit beyond a band for weeks, which is why the level alone is context, not a signal.
When price makes a new high but RSI makes a lower high (or price a new low while RSI makes a higher low), momentum is no longer confirming the move. Analysts treat divergences as early warnings that a trend is tiring - more reliable on the daily timeframe than intraday.
Treat it as momentum context, not a timing tool. Overbought can stay overbought in a bull trend, and oversold can keep falling in a crash. Combine it with valuation (MVRV), flows and sentiment rather than reading it on its own. This page is general information only and not financial advice - see our Disclaimer.