Quick answer
Volatility describes how much an investment's price moves up and down over time. FINRA describes it simply: some days indexes and stock prices go up and other days they go down [1]. Bigger, more frequent swings mean higher volatility.
#How is volatility measured?
The most common yardstick is the standard deviation of returns: how far returns typically land from their average. Another is beta, which FINRA explains measures how a stock moves relative to the market rather than its total volatility [1]. Funds often report both in their materials.
Worked example
Same average, different ride
Two hypothetical investments each average 8% a year over five years. Investment A returns 8%, 6%, 9%, 7%, 10%. Investment B returns 30%, −15%, 25%, −10%, 10%. Each starts with $10,000.
- Average yearly return, A and B
- 8% each
- Standard deviation of A
- 1.58 percentage points
- Standard deviation of B
- 20.19 percentage points
- A after 5 years
- $14,686.98
- B after 5 years
- $13,674.38
B is far more volatile and, despite the same simple average, ends with about $1,000 less, because losses hurt more than equal-sized gains help.
Hypothetical returns calculated in code; real returns vary and can be negative over any period.
#Why does volatility matter to a beginner?
Volatility is a big part of what makes stocks risky in the short run. Investor.gov notes that large-company stocks as a group have lost money on average about one out of every three years [2]. If you might need your money soon, a large drop at the wrong moment can force you to sell low. That is why time horizon matters; see risk tolerance and time horizon.
| Lower volatility | Higher volatility |
|---|---|
| Smaller, steadier price changes | Larger, more frequent price swings |
| Narrower range of likely outcomes | Wider range of outcomes, both up and down |
| Easier to hold through short periods | Harder to hold if you may need the money soon |
#Can you reduce volatility?
You cannot remove it, but you can manage it. FINRA points to diversification across, and within, the major asset classes, while keeping in mind that all investments fluctuate in price [1]. Read more in market volatility explained and diversification explained.
Related terms
Frequently asked questions
Is volatility the same as risk?
Not exactly. Volatility measures price swings. Risk also includes the chance of permanent loss, inflation eating your returns, or not being able to sell, which volatility alone does not capture.
Is high volatility always bad?
It cuts both ways. Bigger swings mean bigger possible gains as well as bigger losses, and the losses matter most when you need to sell during a drop.
Sources
Grade A = primary source (regulator, government agency, official rulebook or the index provider's own documents). Numbers in brackets in the text point here.
- FINRA. Volatility (2026). Accessed 2026-10-03.A
- U.S. SEC — Investor.gov. Stocks (2026). Accessed 2026-10-03.A
This page is general education, not personal financial, tax or legal advice. Figures in worked examples are hypothetical and calculated before taxes and fees unless stated. Rules and limits change; check the linked primary sources for the current version. How we check every page.
