Expected Move Calculator
Calculate the expected price range based on implied volatility. See the 1 and 2 standard deviation moves for any time period.
Enter stock price, implied volatility, and days to expiration, then click Calculate expected move to see the expected price range.
Expected Move Formula
Expected Move = Price × IV × √(DTE/365)
1σ move = 68% probability within range
2σ move = 95% probability within range
Worked Examples
Example 1: Earnings expected move for a $200 stock
A stock trades at $200.00 with implied volatility of 40%. Earnings are in 7 days. You want to know the expected move heading into the report.
- Time scalar = √(7/365) = 0.1385
- 1σ Expected Move = $200 × 0.40 × 0.1385 = ±$11.08
- 1σ Range = $200 − $11.08 to $200 + $11.08 = $188.92 – $211.08
- 2σ Expected Move = $11.08 × 2 = ±$22.16
- 2σ Range = $177.84 – $222.16
There is roughly a 68% chance the stock stays between $188.92 and $211.08 over the next 7 days, and a 95% chance it stays between $177.84 and $222.16.
Example 2: Weekly expected move on a low-volatility ETF
An ETF trades at $450.00 with implied volatility of 15%. You want the 30-day expected move for selling iron condors.
- Time scalar = √(30/365) = 0.2867
- 1σ Expected Move = $450 × 0.15 × 0.2867 = ±$19.35
- 1σ Range = $430.65 – $469.35
- 2σ Expected Move = $19.35 × 2 = ±$38.70
- 2σ Range = $411.30 – $488.70
For a 30-day iron condor, selling the short strikes outside the 1σ range ($430 and $470) gives roughly a 68% probability of keeping full premium.
How to Use This Calculator
- Enter the stock price — the current market price of the underlying asset.
- Enter implied volatility (IV) — the annualized IV percentage, which you can find on your broker's option chain or a site like CBOE.
- Select or enter days to expiration — choose a preset (7, 14, 30, etc.) or type a custom number of calendar days.
- Click Calculate expected move — the calculator shows the 1σ and 2σ price ranges for your chosen period.
- Review the timeframe table — compare 1-day, 7-day, 30-day, and 90-day moves side by side to plan entry and exit timing.
- Use results to set strike prices — sell options outside the expected move range to collect premium with a statistical edge.
Frequently Asked Questions
- What does "expected move" actually mean?
- The expected move is the price range the market implies a stock will trade within over a given time period, based on current implied volatility. A 1 standard deviation move means roughly 68% of the time, the stock will stay within that range. It is not a prediction — it is a probability-weighted estimate derived from option prices.
- Where do I find implied volatility for a stock?
- Most brokerage platforms display IV on their option chains. You can also find it on sites like CBOE, MarketChameleon, or TradingView. Look for the "IV" or "Implied Vol" column next to option strikes. Some platforms show IV rank and IV percentile for additional context.
- How is expected move used in options trading?
- Options sellers use the expected move to choose strike prices for strategies like iron condors, strangles, and credit spreads. By selling strikes outside the expected move, you have a statistical edge — the market implies those strikes should expire worthless more often than not. Buyers use it to evaluate whether the premium they are paying is justified.
- Why does the expected move increase with more time?
- The expected move scales with the square root of time (√DTE). This means doubling the time period does not double the move — it increases it by about 41% (since √2 = 1.414). This reflects the statistical property that random price movements compound slower than linearly over time.
- Is the expected move accurate around earnings?
- IV typically spikes before earnings announcements, which inflates the expected move. After the announcement, IV usually drops sharply ("IV crush"). The expected move around earnings is often a reasonable estimate but can understate tail risk. Stocks can and do move 2 or 3 standard deviations on surprise earnings, so position sizing is critical.