Volatility

How Far Can It Really Go?

Turn implied volatility into a price range for any timeframe. See the 1 and 2 standard deviation zones, odds of hitting a target, and a straddle cross-check.

Not financial advice. This is an educational tool. An expected move is a probability range based on implied volatility, not a prediction, and real prices can move past it. Speak with a licensed financial advisor before trading.

What is an expected move?

Implied volatility (IV) is the market's guess at how much a stock will swing over a year. Scale it down to your timeframe and you get the expected move (a one standard deviation, or 1 SD, range). The price should stay inside it roughly 68% of the time. Two standard deviations (2 SD) covers about 95%.

Options sellers use it to place short strikes outside the range. Buyers use it to judge whether a target is realistic before paying for the contract.

Expected Move Calculator

Enter the price, the implied volatility from your option chain and how many days you care about. The ranges and the bell curve update as you type.

The stock or ETF price right now
From your option chain. 20 to 40 is common
How far out you want the range for
Typical earnings move. 0 means no event in these days
365 is the usual for IV
Typical Move In Dollars (1 SD Move)
$0
Up or down over your timeframe
Typical Move In Percent (1 SD %)
0%
Share of the stock price
Typical Move Per Day
$0
Spread evenly across your days
Likely Range (1 SD, 68%)
-
About 2 times out of 3
Wide Range (2 SD, 95%)
-
About 19 times out of 20
Odds It Lands Outside The Likely Range
31.7%
About one time in three
Where To Sell Options (Short Strikes)

For premium sellers. Pick how sure you want to be the stock stays between your two strikes. It places a put strike below and a call strike above, then checks what a spread of that width should pay.

80 means it should finish between the strikes 8 times in 10
Gap between the strike you sell and the one you buy for protection
From your broker for one put or call spread. Optional
Sell A Put At (Short Put Strike)
-
Below the stock price
Sell A Call At (Short Call Strike)
-
Above the stock price
Chance It Stays Between
-
Both strikes survive
Chance It Touches A Strike (Touch Chance)
-
Either strike, at any point
Most You Can Lose (Per Side, 1 Contract)
-
Width minus credit, times 100
Fair Credit (Rough, Per Side)
-
What the odds say a spread is worth
Target and Straddle Check

Optional. Enter a price level to see the odds of finishing past it, or the at-the-money straddle price to compare against the IV based number.

Above or below the stock price, either works
Call plus put at the strike nearest the stock price. Optional
Finish Above Target
-
Chance it ends there on the last day
Touches It At Any Point (Touch Chance)
-
Rule of thumb, double the finish chance
Move The Straddle Implies
-
About 85% of the straddle price
Distance To Target
-
From the stock price now
Move Needed Per Day
-
Compared with a normal day
Days Until A Coin Flip To Touch It
-
When touching it reaches 50%

Touch chance doubles the finish probability, a common shortcut for the odds the price trades through a level at any point before expiry. The straddle based move is about 85% of the straddle price.

Visualizer

Your expected move drawn to scale, then the odds and timeframe tables. Everything here updates from the inputs at the top.

Bell curve of likely pricesCurrent priceHover for the odds at any price
In plain English: the tall middle of the bell is where the price most likely ends up. The dark shaded zone is the 1 SD range (about 68% of outcomes) and the lighter band is 2 SD (about 95%). Formula: price x IV x square root of (days / year basis). A known event (like earnings) adds its own jump, blended in as the square root of the two squared moves added together. It is a probability range, not a prediction, and a move past it still happens about one time in three.
The Expected Cone

The same range drawn over time. The cone is narrow today and opens up as days pass. Your target price from the panel below shows as a pink line.

Solid lines: likely range (1 SD, 68%)Dashed lines: wide range (2 SD, 95%)Hover to read any day
In plain English: the cone shows how fast uncertainty grows. It widens quickly at first and then more slowly, because the move grows with the square root of time. If a known event is added, the cone jumps wider the day after today. A target line that sits outside the cone is a long shot.
Odds Ladder

The chance of finishing past each price, in half-SD steps, for your days ahead. Darker cells are likelier. The gold rows are the 1 SD and 2 SD levels.

LevelPriceFrom TodayFinish AboveFinish BelowTouch Chance
Same IV, Different Timeframes

Moves grow with the square root of time, so doubling the days does not double the range.

DaysTypical Move (1 SD)Percent1 SD Low1 SD High2 SD Low2 SD High