SVQ · Volatility
IV rank
Also called: implied volatility rank, IVR, IV percentile
IV rank places current implied volatility within its own past range, from 0 at the period low to 100 at the period high.
Definition
IV rank expresses an asset's current implied volatility relative to the highest and lowest values it reached over a look-back window, usually one year. A reading of 0 means implied volatility is at the window's low; 100 means it is at the high.
IV percentile is a related but different measure: the share of days in the window on which implied volatility was below today's level.
Intuition
Raw implied volatility is hard to compare across assets: 30% is high for a broad index and low for a small biotech. Ranking each asset against its own history makes readings comparable and answers a simpler question: is volatility cheap or rich for this asset, by its own standards?
Option sellers often look for high readings and buyers for low ones, but the measure says nothing about why volatility is where it is.
How it's calculated
IV rank = 100 × (IVnow − IVmin) / (IVmax − IVmin)
IV percentile = 100 × (days with IV < IVnow) / (days in window)
Both depend on which implied volatility series is used (for example 30-day constant-maturity at the money, or a specific expiry), on the window length, and on how missing days are handled. Rank uses only two extreme points, so a single spike can pin it low for a year; percentile uses the whole distribution and is less sensitive to one outlier.
Example: if 30-day implied volatility ranged from 15% to 55% over the past year and is 25% today, IV rank is 100 × (25 − 15) / (55 − 15) = 25. If it spent most of the year between 15% and 22%, the IV percentile could still be 85 or higher. The two numbers describe the same day very differently.
How to read it
A high rank with a low percentile usually means one extreme spike stretched the range. Check both, and look at the underlying series before drawing conclusions.
Regimes matter: after a volatility shock, rank can stay low for months even though implied volatility is elevated compared with the calm period before. Pair the reading with realized volatility and the event calendar.
Common mistakes
- Confusing IV rank with IV percentile.
- Comparing ranks computed from different volatility series or windows.
- Reading a high rank as a forecast that volatility will fall soon.
- Ignoring known events, such as scheduled announcements, that justify elevated implied volatility.
In Saqrid
SVQ's Risk Lab includes an IV-rank grid by moneyness and tenor, plus tail metrics and implied-moment time series.
In SVPulse, signed-in users see option-implied volatility, IV rank and the IV-to-realized ratio for covered assets.