Where option premium is richest right now, for option sellers (covered calls, cash-secured puts, credit spreads, iron condors). Sorted by premium score, which blends how high IV is vs the rest of the list, how far IV runs above the stock's realized (historical) volatility, and IV rank. Premium is richest when all three are high: the market is paying you more than the stock has actually been moving. Click a column to re-sort; click a ticker for its full IV history.
Last scan: · 107 tickers with live option quotes · rescans every 6 hours.
IV the yearly move options are pricingIV rank 0 = lowest IV of the year, 100 = highest (needs 20 days of recorded history)IV / HV above 1.2× = options pricing in more movement than the stock has shown
High IV means high risk as well as high premium: it's often high because an event (earnings, FDA decision, lawsuit) is coming. Check the next earnings date before selling, and prefer defined-risk trades (spreads, iron condors) on the most volatile names.
Low IV · Buy Premium
Where options are cheapest relative to their own history and to how much the stock actually moves, for option buyers (long calls or puts, debit spreads, long straddles). Buying when IV is low means you pay less for the same move, and a rise in IV later works in your favour. Sorted from the lowest premium score up.
Last scan: · 107 tickers with live option quotes · rescans every 6 hours.
State Street SPDR S&P 500 ETF T (SPY) · $765.61. Search any ticker above.
Implied volatility (IV) is how much movement the options market is pricing in; historical volatility (HV) is how much the stock actually moved. Both are yearly percentages. Comparing them shows whether options are cheap or expensive.
Implied volatility (30-day, at the money)53.2%Options expiring 2026-10-30 (31 days), the calls and puts nearest today's price. Rough guide: under 20% calm, 20-40% normal for single stocks, 60%+ very volatile.
Expected move by expiry±$118.75±15.5% by 2026-10-30. Options price the stock to stay within this range about two-thirds of the time. Sellers often place short strikes just outside it.
IV rank / percentile (1 year)15 / 27%Where today's implied volatility sits in its past-year range of historical implied volatility (0 lowest, 100 highest), from a full year of the VIX volatility index; percentile = share of days it was lower. Above 50 favours selling premium, below 30 favours buying.
Historical volatility (20 / 30-day)11.1% / 10.0%How much the stock actually moved over the last 20 and 30 trading days, as a yearly rate.
HV rank / percentile (1 year)29 / 14%Where 30-day HV sits in its past-year range. Volatility mean-reverts: very low readings often come before bigger moves.
IV premium (IV − HV)+43.2 ptsPositive = options price more movement than the stock has shown: the edge option sellers collect over time. Negative = options look cheap.
Call IV / put IV51.8% / 54.7%Puts pricier than calls ("skew") means traders are paying up for downside protection, which makes selling puts pay more.
Put/call ratio (volume / open interest)1.05 / 0.00Puts per call at that expiry. Above ~1 leans bearish or hedged; below ~0.7 bullish. Extremes are often read contrarian.
Historical Implied Volatility vs Realized Volatility
Two different things, easy to mix up. Historical implied volatility (lavender) is what option prices were expecting on each past day: the record IV rank is built from. Historical (realized) volatility (blue) is how much the stock actually moved over the prior 30 days. When lavender runs above blue, options were priced for more movement than the stock delivered, which is the gap premium sellers earn.
For SPY the implied line is the VIX (S&P 500 30-day implied volatility), with two full years of history.
SPY volatility, % per yearHistorical implied volatilityRealized volatility (30-day)
IV Term Structure
At-the-money IV for each upcoming expiry. Normally it slopes up (more time, more uncertainty). An inverted curve, with near-term IV above longer-term, means the market expects an event soon (earnings, a ruling). Sellers can collect that inflated near-term premium, but it's inflated for a reason.
The Greeks
The Greeks measure how an option's price reacts to the things that move it: the stock price, time, and volatility. Knowing them is how you pick strikes and expiries on purpose instead of by feel.
How to use the calculator
It works out what an option should be worth, and how that value will change, for any option you describe in the five boxes. Everything updates as you type.
Stock price: the stock's price today (or a price you want to test, like "what if it drops to $90?").
Strike: the strike of the option you're looking at in your broker's option chain.
Days to expiry: calendar days until that option expires.
Implied volatility: the option's IV, shown next to it in your broker's chain. Not sure? Look the ticker up on the Implied Volatility & History tab and use its 30-day IV, press the button below to fill in SPY's numbers, or click any row of the option chain under the summary.
Interest rate: leave it around 4%. It barely changes the result.
Then read the plain-English summary under the boxes, or the table for the exact numbers. All prices are per share: one contract covers 100 shares, so multiply by 100 for the dollar amount. Good experiments: raise the stock price to watch delta climb, cut the days to see time decay speed up, raise IV to see premiums grow.
SPY option chain
The market's real prices for SPY, 16 strikes above and below today's price. Click any row to load that strike, its IV and the days to expiry into the calculator above, then compare the calculator's price with the bid/ask here: they should land close together, and the Greeks tell you how each option will move. Shaded cells are in the money. IV and Δ (delta) are worked out from each option's mid price (or its last trade when the market is closed and there's no live bid/ask), using the same model as the calculator. Search another ticker at the top of the page.
Calls
Puts
OI
Volume
IV
Δ
Last
Bid
Ask
Strike
Bid
Ask
Last
Δ
IV
Volume
OI
Price
Delta
Gamma
Theta / day
Vega / 1% IV
Rho / 1% rate
Call
Put
Delta & gamma across stock prices
The blue line is the call's delta at every stock price; the dot is where your stock price sits. Far below the strike delta is near 0 (the option barely reacts), far above it's near 1 (it moves like the stock). Gamma, the lavender hump, peaks at the strike: that's where delta changes fastest.
Time decay: at-the-money option value vs days left
What an at-the-money call on your stock is worth as expiry approaches, at your IV. The curve bends down in the shaded last 45 days: time decay speeds up, which is why sellers like 30-45 days out and buyers avoid it.
Δ Delta
What: how much the option moves for a $1 move in the stock. A 0.50-delta call gains about $0.50 when the stock rises $1. Calls run 0 to 1, puts 0 to −1.
How it's used: as a rough probability the option finishes in the money: a 0.16-delta put has roughly a 16% chance. Sellers often sell 0.15-0.30 delta strikes; buyers wanting stock-like exposure use 0.70+. Delta is also your share-equivalent exposure: 5 calls at 0.40 delta ≈ 200 shares.
Γ Gamma
What: how fast delta changes as the stock moves. Highest for at-the-money options, and it spikes in the last days before expiry.
How it's used: it's the acceleration. Long options have positive gamma (moves work increasingly in your favour); short options have negative gamma (a move against you snowballs). That's why sellers close or roll positions with ~7-21 days left instead of holding into expiry week.
Θ Theta
What: how much value the option loses each day just from time passing, all else equal. Shown as dollars per share per day.
How it's used: theta is the option seller's income and the buyer's cost. Decay accelerates in the final 30-45 days (see the chart), which is why sellers typically open trades 30-45 days out and buyers prefer 60+ days to give the trade time.
ν Vega
What: how much the option's price changes when implied volatility moves 1 percentage point. Largest for at-the-money and longer-dated options.
How it's used: sellers are short vega: they profit when IV falls (e.g. the "IV crush" after earnings), so they sell when IV rank is high. Buyers are long vega and want IV low when they buy. The scanners above find both.
ρ Rho
What: sensitivity to interest rates, per 1 percentage point. Calls gain and puts lose when rates rise.
How it's used: minor for short-term trades; it matters for long-dated options (LEAPS) and when rates move sharply.
Putting it together as a premium seller
Sell when IV rank is high (you're short vega, so you want IV to fall), about 30-45 days out (theta decay is fastest, gamma still manageable), at 0.15-0.30 delta (roughly 70-85% chance of expiring worthless), with the strikes outside the expected move. Take profits around 50% of the maximum and close or roll by ~21 days left to avoid the gamma spike. Keep total short delta in check across positions.
Option Analyzer
See what happens to an option's value, and your profit or loss, when the stock moves, implied volatility (IV) changes, and time passes. Describe the option in the top row, then drag the three sliders. Everything is per contract (100 shares).
Option
Position
Leave "price paid" empty to use today's fair value. Enter what you actually paid (or received, if you sold) to see your real profit or loss.
Profit / Loss Grid
Profit or loss for your whole position at every combination of stock move (down the side) and IV change (across the top), after the days passed on the slider. Green = profit, red = loss; the outlined cell is your current slider setting. Click any cell to jump to it.
Why the stock can go your way and you still lose
Set the IV change to −10 with a small favourable stock move: after earnings, IV often collapses ("IV crush"), and the drop in vega value can outweigh the gain from the move. That's why buyers prefer low IV and sellers like high IV.
Time works against buyers
Slide "days passed" toward expiry with no stock move: a bought option loses value every day (theta), faster at the end. For a seller the same slide is profit.
Reading the breakdown
The profit or loss is split into what came from the stock move (delta and gamma), the IV change (vega) and time (theta), so you can see which one drove the result.
Strategies
The most-used option strategies, grouped by what they're for. Each is drawn as a profit/loss diagram on an example $100 stock: green is where you make money, red where you lose, dotted lines mark the breakevens. Per-share values; one contract = 100 shares. Jump to a group below, or filter by the market you expect or the IV environment.
* Rule-based heuristic from the metrics above. This is educational information, not financial advice.