What Is Average Daily Volume (ADV)?

Average daily volume — ADV — is the most-used number nobody bothers to define: a stock's typical shares traded per day, averaged over some trailing window. It is the denominator inside days to cover, the baseline inside relative volume, and the liquidity test inside every screener — which means every one of those numbers inherits ADV's quiet choices: which window, which sessions, shares or dollars. This page defines it properly and shows why the choices matter.

The number itself, measured

Twenty regular-hours sessions, four familiar names plus a deliberately thin one:

SELECT ticker,
       round(sumIf(toFloat64(volume), (toHour(window_start) * 60 + toMinute(window_start)) BETWEEN 810 AND 1199) / 21 / 1e6, 2) AS adv_shares_m,
       round(sumIf(toFloat64(close) * toFloat64(volume), (toHour(window_start) * 60 + toMinute(window_start)) BETWEEN 810 AND 1199) / 21 / 1e9, 2) AS adv_dollars_bn
FROM global_markets.delayed_stocks_minute_aggs
WHERE ticker IN ('SPY', 'AAPL', 'MU', 'KO', 'CATO')
  AND window_start >= '2026-06-11 13:30:00' AND window_start < '2026-07-11 00:00:00'
GROUP BY ticker
ORDER BY adv_shares_m DESC

The table carries this page's whole argument. SPY and MU sit within a share or two of each other in share terms (43.82M vs 40.01M) — but the dollar column splits them wide apart: 32.56B against 42.37B a day. Shares measure activity; dollars measure money. And at the bottom, CATO trades 0.04 million shares a day — the kind of tape where a single institutional order IS the day's volume, and where trading costs live in a different universe.

The window is a choice, and it leaks into everything

Twenty sessions is the common convention (a trading month); ten, thirty, sixty-five, and ninety all circulate. The window decides how fast ADV forgets: a short window snaps to a news week and then calls the aftermath "normal"; a long window keeps calling a structurally re-rated stock "unusual" for months. MU is 2026's live example — a name whose tape re-rated so hard mid-year that its trailing-month ADV would have looked like an anomaly to its trailing-quarter self, receipts throughout its June deep-dive. When two sources disagree about a stock's ADV, the window is the first suspect; whether extended-hours volume is included is the second (this page's panel is regular-hours only, and says so).

Where ADV silently decides other numbers

• Days to cover = short interest ÷ ADV. A volume spike shrinks the ratio with zero change in the short position — the denominator did it.
• Relative volume = today's pace ÷ ADV. Same number, opposite role: here ADV is the baseline being beaten.
• Liquidity screens ("only names above 1M ADV") — every backtest and screener carries one, and survivorship quietly follows: names enter such screens by having their most dramatic weeks.
• Position sizing — the institutional rule of thumb of trading only a small percentage of ADV per day is why big funds simply cannot own certain small stocks: weeks of the whole tape's volume would be needed to build or exit a position.

Reading ADV like a practitioner

Three habits close the gap between knowing the definition and using it. Always pair share ADV with dollar ADV — the panel above shows two names nearly tied in shares and far apart in money, and the money column is the one your order cares about. Distrust ADV immediately after events — a stock that just had its heaviest week ever carries an inflated ADV for exactly one window-length afterward, which mechanically deflates its relative volume and days to cover until the spike ages out; both metrics look "calmer" for weeks purely by arithmetic. Check ADV against the calendar — expiration Fridays, rebalance days, and index-change dates inflate everyone's volume at once (witching days most of all), so a market-wide heavy day says nothing about any single name's story.

Average daily volume FAQ

What is a good average daily volume?

For tradability, the useful floor is dollars, not shares: millions of dollars a day means retail-size orders trade without moving the price. The panel above shows the range — from index-fund oceans to a thin name where every order matters.

What window is ADV measured over?

Most commonly 20 trading sessions (about a month), but 10-, 30-, 65- and 90-day versions all circulate, and they disagree after any volume shock. Check the window before comparing sources.

Is ADV shares or dollars?

Traditionally shares, but dollar ADV is the better liquidity measure across stocks — a million shares of a $5 stock and a $700 ETF are different oceans. The panel above shows both so the difference is concrete.

Does ADV include premarket and after-hours volume?

Depends on the source — this page's figures are regular-hours only. Extended sessions add a few percent for most names, concentrated around news days; the extended-hours guide measures it.

Every figure is a stored, versioned query — expand the SQL, or compute any window for any ticker on the Strasmore terminal.