Glossary · Defined term
Volume
Volume is the number of shares traded in a security over a given period, usually one trading day. Definition, how to read it, and an example.
Last updated Oct 2, 2026
What it means
Volume is the number of shares traded in a security over a given period, usually one trading day. High volume signals strong investor interest and generally means orders fill quickly at prices close to the quote, while low volume can let even modest orders push the price around. Traders watch volume alongside price: a price move on heavy volume suggests conviction, while the same move on thin volume may be noise. Average daily volume is the standard liquidity gauge for a stock. Sudden volume spikes often accompany news, earnings, or the entry of large institutional buyers or sellers.
An example
For illustration, a stock averaging 1 million shares a day suddenly trades 12 million shares after an earnings surprise. That surge tells the market the price move has broad participation behind it. A stock averaging 5,000 shares a day, by contrast, might jump 8 percent on a single large order that would barely register elsewhere.