Implied Volatility (IV) Explained: 30-Day At-the-Money IV30

Implied volatility (IV) is the amount of price movement that option prices imply, quoted on a yearly scale. Higher IV means options cost more relative to the stock or ETF, because the market is pricing bigger possible moves in either direction. Vyreon measures one standardized number per security for each trading session: 30-day at-the-money implied volatility, or IV30.

What Implied Volatility Measures

An option's price depends on the underlying price, the strike, the time to expiry, interest rates, dividends, and one unknown: how much the price may move. Implied volatility is that unknown, solved backward from the option's market price with a pricing model.

Because IV is annualized, it scales with the square root of time. Illustrative example: an IV of 20% corresponds to a one-standard-deviation move of about 20% × √(30/365) ≈ 5.7% over 30 days.

Every option has its own IV, and the numbers differ by strike (IV skew) and by expiry (IV term structure). To track one series over time, you need a fixed rule for which point to read. Vyreon's rule is "at the current price, 30 days out".

How Vyreon Measures It (IV30)

Model IVs: Vyreon solves each option's IV from closing quotes with its own model. It uses the day's closing price, the federal funds rate, and a carry implied from put-call parity for each expiry.
At the money, per expiry: it uses put IV for strikes below the current price and call IV for strikes above it, which are usually the out-of-the-money options. It takes the nearest supported strike on each side within about 5% of spot and interpolates variance in log strike to the spot strike. If a strike sits exactly at spot with both a call and a put, those two are averaged in variance.
To 30 calendar days: it takes the nearest expiries on either side of 30 days (no more than 42 days apart) and interpolates in total variance (variance × time). Interpolating the IV numbers directly would be wrong.
No usable 30-day bracket: some ETFs list only monthly expiries, so for part of each month nothing expires within 30 days, or the expiries on either side are more than 42 days apart. In that case Vyreon uses the at-the-money IV of the expiry nearest 30 days, if it is 21 to 45 days out, as is, rather than adjusting it to exactly 30 days. The expiry used is shown with the value.

If none of these rules can be met, the value is withheld with a reason. It is never carried forward from an earlier day or filled in.

Is Implied Volatility High Right Now?

A single IV number has little meaning on its own. 25% is calm for a volatile growth stock and extreme for a bond ETF. The useful comparison is with the same security's own history, which IV rank and IV percentile provide.

Is This The VIX?

No. The VIX is a model-free index of S&P 500 option variance. Vyreon's IV30 is an at-the-money model estimate for each individual security. It is also not a data provider's or broker's IV figure, so compare IV30 only with IV30.

What Implied Volatility Does Not Tell You

It does not predict direction. High IV means bigger moves are priced in, up or down.
It is a price of risk, not a forecast. It includes risk premiums and the supply and demand for options.
It is not realized volatility, which measures how much the price actually moved. See IV vs realized volatility.

Sources

Fischer Black and Myron Scholes, "The Pricing of Options and Corporate Liabilities", Journal of Political Economy (1973), and Robert C. Merton, "Theory of Rational Option Pricing", Bell Journal of Economics and Management Science (1973): the pricing model from which implied volatility is solved.
John C. Hull, Options, Futures, and Other Derivatives (Pearson, many editions): implied volatility, the volatility smile and term structure.
Cboe, VIX White Paper: the methodology of the Cboe Volatility Index, a model-free 30-day measure built from many S&P 500 option strikes and interpolated in variance between two expiries.