What Is Relative Volume and Why Scan for It?
Relative volume (RVOL) compares today's traded shares to average volume at the same clock time—or full-day average for end-of-day scans. RVOL of two means twice normal participation. Unusual volume often precedes or accompanies institutional activity, news absorption, and sustained trends. Percent change alone misleads: a five percent move on double volume differs from five percent on half volume. RVOL scanners prioritize participation-confirmed movers over thin air pumps.
Use time-of-day adjusted RVOL intraday—raw volume at nine thirty always looks elevated versus noon.
What RVOL Thresholds Do Traders Use?
Day trade momentum: RVOL above two by ten a.m., rising. Breakout confirmation: RVOL above one point five on breakout bar. Swing unusual activity: full-day RVOL above one point five before close. Thresholds vary by universe—liquid ETFs rarely hit four RVOL; small caps often do on news. Combine minimum absolute dollar volume so RVOL on two hundred thousand share average does not flag illiquid traps.
Rising RVOL on pullbacks in uptrends flags accumulation—worth a dedicated scan preset.
How Do You Build a Relative Volume Scanner?
Base liquidity: price above five, average volume above one million. RVOL greater than two, percent change aligned with strategy direction. Optional: price above VWAP for long bias. Sort by dollar volume times RVOL for impact. Alert on cross—RVOL newly above two—not static membership. Intraday refresh every one to three minutes. Pair with sector filter when one group leads the market. Export top ten to watchlist for chart pattern review.
Add maximum float filter when hunting sustained trends—extreme RVOL on low float often mean reverts fast.
How Does RVOL Confirm Other Setups?
Breakout scans require RVOL spike on break bar. Gap continuation needs RVOL holding above one point five first thirty minutes. Pullback entries want RVOL contraction on dip and expansion on bounce. Reversal fades want declining RVOL into resistance. RVOL is a participation lens layered on price structure—not a standalone entry. Chart must still show clear level and stop.
When price makes new high but RVOL diverges lower, tighten stops—move may lack sponsorship.
What Mistakes Do Traders Make With RVOL Scans?
Using full-day average at nine thirty without time adjustment. Ignoring dollar volume on low-float RVOL spikes. Chasing RVOL after move is extended. Treating RVOL as buy signal without price setup. Running RVOL scan without direction filter in strong bear days. RVOL scanner strategies work when thresholds match your style and every alert still passes chart qualification.
Compare RVOL to sector peers—leadership within a hot group matters more than isolated RVOL in a dead sector.