What is the expected move?
Updated 6 June 2026 · by Theo Chen
The expected move is the size of the price swing — up or down — that the options market is pricing into a stock by a given expiration. It is roughly a one-standard-deviation range: about a 68% chance the stock finishes inside it. Read straight from option prices, it reflects what the market expects now, not anyone's forecast.
Want the expected move for a specific stock? Enter the price, implied volatility and days to expiration and the calculator returns the dollar move and the one-standard-deviation range.
Open the Expected Move Calculator →What the expected move tells you
The expected move answers two questions at once: how far the market thinks the stock could travel, and how much it is charging for that movement. A wide expected move means options are pricing in heavy uncertainty and premium is rich; a narrow one means a calm, cheaper market. As a one-standard-deviation band it carries about a 68% chance the stock stays inside and about a 32% chance it breaks out — so a price finishing outside the range is not a surprise; it happens roughly one time in three.
How the expected move is calculated
There are two common methods, and they agree closely:
- The straddle approximation: the expected move is roughly the price of the at-the-money straddle — the call plus the put at the current strike — because that is what the market charges for a move in either direction.
- The volatility formula: expected move ≈ stock price × implied volatility × √(days to expiration ÷ 365), with IV as a decimal. This scales the annual volatility down to the period you care about.
A worked example
Take a stock at $100 with implied volatility of 30% and 30 days to expiration. Using the formula: $100 × 0.30 × √(30 ÷ 365) = $100 × 0.30 × 0.287 = about $8.60. So the market is pricing a one-standard-deviation move of roughly $8.60 — a range of about $91.40 to $108.60, with near 68% odds of finishing inside. If the 30-day at-the-money straddle costs about $8.60, the straddle method gives the same read.
How do traders use the expected move?
Sellers place short strikes outside the expected move so a normal-sized swing stays in their profit zone — it is the natural way to choose iron condor or strangle strikes. Buyers use it to check whether a move they expect is already priced in. Around earnings, the at-the-money straddle prices the reaction the market anticipates, so you can compare it with your own view. Pair it with the probability calculator to turn the range into the odds of touching or finishing beyond a strike.
The bottom line
The expected move is a one-standard-deviation range, so the stock finishes outside it about one time in three - treat it as a probability band for placing strikes or judging if a move is priced in, not as a ceiling on how far price can travel.
Frequently asked questions
What is the expected move in options?
The expected move is the size of the swing — up or down — that the options market is pricing into a stock by a given expiration. It is roughly a one-standard-deviation range, meaning there is about a 68% chance the stock finishes inside it and about a 32% chance it lands outside. It is read straight from option prices, so it reflects what the market currently expects, not a forecast.
How do you calculate the expected move?
Two common ways. The quick one: the expected move is approximately the price of the at-the-money straddle (the call plus the put at the current price), since that is what the market charges for a move in either direction. The formula version: expected move ≈ stock price × implied volatility × the square root of (days to expiration ÷ 365), with IV as a decimal.
What does the expected move tell you?
It tells you the range the market thinks is likely, and how much it is paying for movement. A wide expected move means options are pricing in big uncertainty (and premium is rich); a narrow one means a quiet, cheap market. Sellers use it to place strikes outside the likely range; buyers use it to judge whether a move they expect is already priced in.
How accurate is the expected move?
It is a probability range, not a guarantee. As a one-standard-deviation band, the stock should finish inside it roughly 68% of the time and outside it about 32% of the time — so being wrong one time in three is normal and expected. It also assumes a roughly normal distribution, which understates the odds of rare large moves like gaps and crashes.
How do you use the expected move for earnings?
Before earnings, the at-the-money straddle prices the reaction the market expects from the report. If a stock's straddle implies a $6 move and you only expect $3, options look expensive to buy; if you expect $10, they may be cheap. Many sellers set iron condor or strangle short strikes just outside the expected move so a normal-sized reaction stays in their profit zone.
Related questions
- What is implied volatility, the input behind the expected move?
- What is a straddle, the trade that prices the expected move?
- How do I place iron condor short strikes outside the expected move?
- How do I choose a strike price using the expected move?
Related tools and guides
Size the move for any stock in the Expected Move Calculator, turn the range into odds with the Probability Calculator, and check whether IV itself is high or low with the IV Rank Calculator. Then place your strikes with the Iron Condor Calculator.
Educational explainer only — not financial advice. The expected move is a probability estimate that assumes a roughly normal distribution and understates rare large moves. Confirm the mechanics and size positions to your own risk tolerance.