Volatility, explained the way it behaves
Implied, historical and realised volatility. The smile, the skew and the surface. The term structure, India VIX, and the regimes that decide what any of it means. Every diagram on this site is computed by our own pricing engine — the same engine the calculators run on, so a tool here can never disagree with a page here.
What is volatility?
The one-sentence answer, and the picture that makes it stick.
Quick answer: Volatility measures how much an asset's price moves, expressed as the annualised standard deviation of its returns. It describes the journey, not the destination — two assets can start and finish at exactly the same price while one of them was far more volatile along the way. Volatility says nothing whatsoever about direction.
Same start. Same finish. Utterly different experience.
Two illustrative NIFTY paths over 120 trading days, forced to end at the same level.
That is the whole idea. Everything else on this site — implied volatility, the skew, the term structure, India VIX — is a refinement of the question how do we measure the journey, and what is it worth?
Why volatility matters
Three reasons, and the third is the one that justifies a whole website.
It is most of an option's price
An out-of-the-money option has no intrinsic value at all. Its entire premium is a bet on volatility. Buying one is a volatility trade wearing directional clothing — which is the most common way to be right about direction and still lose money.
It determines how much you can hold
A position sized correctly for a 10% volatility market carries roughly three times its intended risk at 26%. Volatility does not politely announce the change: it goes up by the escalator and down by the stairs.
It is the one thing that is forecastable
Large moves follow large moves, of either sign. Small follow small. Volatility clusters and it mean-reverts. Direction does neither. That single asymmetry is why a volatility forecast is a reasonable thing to attempt and a price forecast usually is not.
The volatility dashboard
Three readings, three different questions. Change them and watch the regime change.
Volatility regime dashboard
Runs entirely in your browser. The level asks how much movement is priced; the slope asks whether the market thinks that level is temporary; the premium asks whether options cost more than the underlying has been delivering.
The five bands — complacent, normal, elevated, stressed, crisis — are conventions calibrated to NIFTY, not laws. Everything here is a description of where the market has been. Regimes are named after the fact: nobody can reliably say what regime they are in today, because the defining feature of a regime change is that it has not been confirmed yet. Read the full page →
Three routes through the library
Pick the one that matches where you are, not where you would like to be.
You have heard "IV crush" and want to know what actually happens
- What is Volatility? — the journey, not the destination
- Standard Deviation — the maths under the whole subject
- Implied Volatility — a price, not a forecast
- Expected Move — turning IV into a range
- IV Crush — why being right about direction is not enough
- India VIX — one number for the whole chain
- The IV cheat sheet — it on one screen
You trade options and want the shapes to stop being decoration
- HV vs IV — the comparison almost everyone gets wrong
- IV Rank and IV Percentile — and why they disagree
- Volatility Skew — the most important page on this site
- Term Structure, Contango, Backwardation
- IV and Vega — why √T decides which option you want
- IV Around Events — the Indian event calendar
- Volatility Risk Premium — small, positive, dangerous
You manage a book and need the model's failure modes, not its features
- Volatility Surface — and why no model fits and hedges it at once
- Sticky Strike vs Sticky Delta — is your hedge a hedge?
- Forward Volatility — variance adds, volatility does not
- Gamma Scalping and Delta Hedging
- Volatility Arbitrage — the word is doing dishonest work
- Dispersion Trading — short correlation, and correlation goes to one
- Crisis Volatility — where every assumption fails together
The three shapes to recognise on sight
If you take nothing else from this site, take these.
1. The skew — implied volatility across strikes
One NIFTY expiry, spot 24,000. The flat grey line is what Black–Scholes assumes.
2. The term structure — implied volatility across expiries
The same underlying, in a calm market and a stressed one.
3. IV crush — implied volatility through an event
Twenty sessions before a scheduled event, to fourteen after.
The eight sections
Sixty-eight concepts, each with a one-sentence answer, the formula with every symbol defined, an original computed diagram, worked NIFTY examples, its limitations, and at least twenty FAQs.
Core Volatility
8Volatility is one word doing eight different jobs. Historical, realised, implied, expected, forward, annualised and intraday — and why they disagree on the same afternoon.
Implied Volatility
11How IV is solved for, why it changes, expansion and crush, event and earnings volatility, and the smile, skew and surface it forms across strikes and expiries.
Volatility Metrics
8IV Rank, IV Percentile, HV vs IV, the volatility risk premium, expected move, standard deviation, variance and realised variance — each defined, computed and criticised.
Term Structure
8Volatility has a shape in time. Contango, backwardation, the calendar and expiry structure, the volatility cone, event premium and rolling volatility.
Volatility Indices
8India VIX and CBOE VIX, how they are constructed, VVIX, VIX futures and options, the VIX term structure — and why the "fear index" label misleads.
Volatility Strategies
9Long and short volatility, long and short vega, gamma scalping, delta hedging, volatility arbitrage, dispersion and calendars — concepts and their real failure modes.
Volatility & Options
9How IV drives premium, theta and vega; how it behaves before and after expiry; and what it actually does around RBI policy, the Union Budget and election results.
Market Regimes
7Low and high volatility, trending and range-bound markets, crisis volatility, mean reversion and clustering. Volatility is not a number; it is a state.
Featured concepts
The pages that most often change how people think.
Volatility Skew
Out-of-the-money puts print higher implied volatility than out-of-the-money calls. Three explanations, all partly true, and practitioners disagree about the weights.
Volatility Risk Premium
Small, positive and frequent. The losses are large, negative and rare. That asymmetry — not the positive average — is the entire story of short volatility.
Volatility Clustering
Volatility is persistent and genuinely forecastable; direction is neither. That single asymmetry is the reason this website exists.
Sticky Strike vs Sticky Delta
Which regime holds decides whether a delta-hedged book is actually hedged. The market switches without announcing it.
Forward Volatility
Variance adds across time; volatility does not. A gently upward-sloping curve can imply a surprisingly expensive forward window.
IV Around Election Results
The largest scheduled volatility event in the Indian market — and the most expensive way to be long volatility.
Reference & tools
For when you already understand the concept and just need the number.
Volatility Cheat Sheet
The nine facts that do most of the work, the five regimes, and the things that are never true.
Comparison Matrix
Nine quantities, all called "volatility", that are not the same thing. The fastest way to know which one a sentence means.
Formula Reference
Every formula on this site, generated from the concept pages themselves, with every symbol defined exactly once.
Implied Volatility Calculator
Type an option's price, get the volatility the market is charging. Solved by bisection, in your browser.
Expected Move Calculator
Turn an implied volatility into the price range the option market is actually pricing.
Volatility Glossary
Every term, from "annualised volatility" to "vomma", defined in plain English and linked to the page that explains it properly.
What this site will never tell you
Every page states its assumptions and the exact conditions under which the concept stops being true, because a measure you cannot criticise is a measure you cannot use. Read our Methodology for the model and its limits, and our Editorial Policy for the standards this site holds itself to.