Relative volume compares how much a stock is trading now vs its usual pace. High RVOL means it’s “in play” — the fuel small-cap movers run on. Enter a ticker to see its volume and dollar volume for the last session, week, month and year, each against an average session.
Checking volume for MRK…
⚠ End-of-day data — this compares the last full session’s volume to the trailing average, not live intraday RVOL. Real-time intraday relative volume is on the roadmap. RVOL ≥ 2-3× often flags a stock in play; ≥ 5× is extreme.
Each period’s average session against the average session in the 252 sessions (one trading year) before it, so a period is never compared with itself. The year row is compared with the year before it.
| Period | Sessions | Shares | Dollar volume (est.) | Per session | vs average session before |
|---|---|---|---|---|---|
| Latest session 1 session | Oct 9 | 9.3M | $1.35B | 9.3M $1.35B | 0.82× −18% avg 11.3M · $1.31B, Oct 8, 2025 – Oct 8, 2026 |
| Last week 5 sessions | Oct 5 – Oct 9 | 41.6M | $5.93B | 8.3M $1.19B | 0.73× −27% avg 11.3M · $1.31B, Oct 2, 2025 – Oct 2, 2026 |
| Last month 21 sessions | Sep 11 – Oct 9 | 206.6M | $30.15B | 9.8M $1.44B | 0.85× −15% avg 11.6M · $1.29B, Sep 10, 2025 – Sep 10, 2026 |
| Last year 252 sessions | Oct 9, 2025 – Oct 9, 2026 | 2.84B | $329.94B | 11.3M $1.31B | 0.80× −20% avg 14.1M · $1.24B, Oct 7, 2024 – Oct 8, 2025 |