Last captured reading, as of 13 Nov 2026, 23:00 IST — live values load in a moment.
Model implies counter-trend dealer hedging. Implied by the assumed dealer sign — not measured.
What is Gamma Exposure (GEX)?
Gamma exposure (GEX) measures how much delta hedging option dealers and market makers must do as Bank Nifty moves. Every option has gamma — the rate at which its delta changes with the underlying. When you add up the gamma of every open contract, weighted by open interest, you get a map of where hedging flows will be strongest. Those flows are large enough to shape intraday behaviour: they can pin the index to a strike, dampen a move, or pour fuel on one.
The concept was formalised by SqueezeMetrics in their original GEX white paper (2017), which showed that aggregate dealer gamma explains a meaningful share of S&P 500 behaviour. Later work — including ALpresi Research — found that the daily change in GEX explains same-day returns roughly three times better than the level itself, which is why this dashboard tracks ΔGEX momentum as a first-class number.
How to read the Bank Nifty GEX dashboard
The bar chart shows net GEX per strike: green bars are strikes where dealer hedging stabilises price, rose bars where it amplifies moves. Four levels matter most:
- Net GEX and regime — the sign and size of total dealer gamma. Long gamma compresses ranges; short gamma expands them.
- Gamma flip — the index level where net dealer gamma changes sign. Crossing it often changes the day's character from mean-reverting to trending.
- Call wall — the biggest call-gamma strike above spot; a common resistance zone and expiry-pinning magnet.
- Put wall — the biggest put-gamma strike below spot; a common support zone. A close beyond a wall can accelerate as hedges unwind.
The chart below the profile shows how net GEX evolved through the session — watching it flip sign intraday is often more useful than any single reading.
Dealer gamma regimes at a glance
| Regime | Dealer hedging | Typical behaviour |
|---|
| Strong long gamma | Sell rallies, buy dips | Tight ranges, pinning near big strikes |
| Long gamma | Counter-trend | Mean reversion favoured |
| Flip zone | Unstable | Whipsaw-prone, regime can change mid-session |
| Short gamma | Chases price | Ranges expand, breakouts follow through |
| Strong short gamma | Amplifies every move | Trending, high-volatility days, squeeze risk |
How we calculate Bank Nifty GEX
For each strike and expiry we solve Black-Scholes implied volatility from live option prices, compute gamma, and aggregate: GEX = Γ × OI × Spot² × 1%, with calls positive and puts negative (dealers assumed net long calls, net short puts). Values are expressed in ₹ crore of delta-hedge notional per 1% index move. The gamma flip is found by re-pricing the entire chain across a grid of hypothetical spot levels and interpolating where net GEX crosses zero.
GEX numbers differ across websites — sometimes by large factors. The usual reasons: open interest counted in units vs contracts (a fixed multiple of lot size), nearest-expiry vs all-expiry scope, and different gamma inputs. Levels that don't depend on scale — the gamma flip, the call and put walls, and the regime — are directly comparable across sources, and those are what we recommend trading from.
Methodology last reviewed July 2026 · Symbols covered: Nifty, Bank Nifty, Sensex, FinNifty, Midcap Nifty, Bankex.
Bank Nifty GEX — Frequently Asked Questions
What is GEX (gamma exposure) in options trading?
GEX estimates how much delta hedging option dealers must do when the index moves. It aggregates the gamma of every open option contract, weighted by open interest. When dealer gamma is large, hedging flows are big enough to influence intraday behaviour — dampening moves in long-gamma conditions and amplifying them in short-gamma conditions.
Is positive GEX bullish or bearish?
Neither — GEX describes expected volatility behaviour, not direction. Positive (long-gamma) GEX implies dealers sell rallies and buy dips, which would compress ranges and favour mean reversion. Note the word implies: the sign is assumed, not measured (see "What could make this whole chart wrong?" below), so treat it as one hypothesis about the day rather than a reading.
What does negative GEX mean for Nifty?
Negative GEX means that under our sign assumption dealers are net short gamma: they would sell as the index falls and buy as it rises, adding fuel to the move. In US index data that regime is associated with expanding ranges and clustered volatility. We have not yet published a scorecard showing it holds on Nifty, so we do not claim it does — see "What could make this whole chart wrong?" below.
What is the gamma flip level?
The gamma flip (zero-gamma level) is the index level where aggregate dealer gamma changes sign under our assumptions. We compute it by re-pricing the whole option chain across a grid of hypothetical spot levels and finding where net GEX crosses zero. It is a model output, not an observable, so we publish it as a band rather than a single number: the band is the range the level moves to when the implied vol surface is shifted ±10% and tilted ±10%. It also drifts through the session as spot, IV and open interest change, which is why the Spot vs Gamma Flip panel plots the whole day rather than quoting one level.
What are the call wall and put wall?
The call wall is the strike above spot with the largest call gamma — heavy dealer hedging there often makes it act as resistance and an expiry-pinning magnet. The put wall is the mirror below spot: the strike with the largest put gamma, which frequently behaves as support. Moves beyond a wall can accelerate as hedges unwind.
How is Nifty GEX calculated?
For every strike and expiry we solve implied vol from live option prices, compute Black-Scholes gamma, and multiply by open interest and by Spot² × 1%, with calls positive and puts negative. Values are ₹ crore of delta-hedge notional per 1% index move — the methodology of the original SqueezeMetrics GEX paper. The calls-positive/puts-negative step is the assumption everything else rests on; it is discussed in full in the next answer.
What could make this whole chart wrong?
The dealer sign. GEX requires knowing whether dealers are long or short each contract. US vendors anchor that on CBOE/NYSE Open-Close data, which reports trade side. NSE publishes nothing equivalent, so like every Indian GEX chart we apply the US convention — dealers long calls, short puts — without being able to verify it. If Indian flow inverts it (retail and prop writing calls rather than buying them), every bar on this chart flips sign and the flip level moves somewhere else entirely. Three further caveats we think are fair: the smooth bell shape of the |GEX| overlay is partly an artifact of Black-Scholes gamma being bell-shaped, not evidence of structure; near-expiry gamma is a spike at ATM, so a 0–1 DTE profile is largely a map of one settlement (we show the DTE and the ATM concentration so you can judge); and a level that only exists for the days until the next weekly expiry is this week's positioning, not a standing feature of the market. This critique is set out at length by ALpresi Research, and we think it is largely correct.
Is this GEX data live? How often does it update?
Yes — the dashboard is live for everyone, updating every few seconds during market hours, with intraday ΔGEX momentum. No login is required to view it. Creating an account is free and unlocks the full trading platform.
All figures are derived, computed values provided for informational and educational purposes only — they do not constitute investment advice or a recommendation to buy or sell any security. Quintal Mind is not a SEBI-registered research analyst or investment adviser. Accuracy and completeness are not guaranteed; consult a SEBI-registered investment adviser before trading. Derivatives trading involves substantial risk of loss.