How far can this stock move by options expiration based on implied volatility?

Multiply the stock price by implied volatility (as a decimal) and by the square root of days to expiration divided by 365. That gives the 1 standard deviation expected move, a statistical estimate covering roughly 68% of outcomes under a lognormal price model, not a prediction of direction.

Does the expected move predict which way the stock will go?

No. It only estimates how far the stock might travel in either direction. It says nothing about whether that move is more likely to be up or down.

Expected Move Calculator: How Far Can This Stock Move by Expiration?

Enter the Option's Numbers

Your Result

Fill in the fields on the left and click Calculate to see the estimated expected move range.

How this is calculated

The 1 standard deviation expected move uses the standard approximation: stock price × (implied volatility ÷ 100) × square root of (days to expiration ÷ 365).
Under a lognormal price model, this range is where the stock statistically has roughly a 68% chance of finishing by expiration, and the wider 2 standard deviation range (double the 1 SD move) covers roughly 95%. These are statistical approximations, not predictions of what the stock will actually do.
This calculation assumes implied volatility stays constant between now and expiration, which it rarely does in practice. Volatility can rise or fall sharply around earnings, news, and macro events.
Use this to sanity-check whether a strike you're considering is inside or outside a realistic move range, not as a forecast of direction. It says nothing about whether the stock goes up or down, only how far it might travel either way.

Risk & liability disclaimer: This calculator produces a statistical estimate based on the inputs you provide and a standard volatility approximation. It is not a prediction of future price, not financial advice, and does not guarantee any trading outcome. Implied volatility itself is an estimate derived from option prices and can change at any time. Trading Habits is not a broker-dealer, registered investment adviser, or tax professional, and is not affiliated with any broker, exchange, or data provider. Always verify results independently and consult a licensed professional before making any trading or financial decision. You could lose some or all of the capital you trade with.

How far can this stock move by options expiration based on implied volatility?

Enter the Option's Numbers

Your Result

How this is calculated

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