# Gamma Exposure — StockMojo > Dealer gamma hedging with Call Wall and Put Wall - Live page: https://stockmojo.in/gamma-exposure - Content last updated: 2026-07-02 - Platform: StockMojo — free options analytics for Indian markets (NSE F&O) This is a machine-readable markdown mirror of the live tool page. The live page shows real-time NSE data during market hours (09:15-15:30 IST) and supports 200+ F&O symbols via per-symbol URLs like https://stockmojo.in/gamma-exposure/banknifty. ## Frequently asked questions ### What is Gamma Exposure (GEX)? Gamma Exposure measures how much dealers (option market makers) must hedge as the underlying moves. Call GEX carries a positive sign and Put GEX a negative sign (the standard dealer convention — dealers are assumed long calls, short puts). Positive GEX means dealers are net long gamma — they sell rallies and buy dips, which dampens volatility and pins the spot. Negative GEX means dealers are short gamma — they buy rallies and sell dips, which amplifies trends. ### What does the Net GEX value tell me? Net GEX is the signed sum across all strikes: Σ(CE GEX + PE GEX), where PE GEX is already a negative number — so it works out to call GEX minus put GEX in absolute terms. A positive number means the call side of dealer hedging dominates — expect mean reversion and tighter ranges. A negative number means the put side dominates — expect trending moves and wider ranges. The Nifty Net GEX usually stays positive during calm regimes and flips negative ahead of sharp moves. ### Why is Put GEX shown as a negative number at each strike? The minus sign is the dealer-positioning convention (SqueezeMetrics / SpotGamma standard), not the option's mathematical gamma — Black-Scholes gamma is positive for both calls and puts. Dealers are assumed net long calls and net short puts, so call OI contributes stabilising (positive) dealer gamma while put OI contributes destabilising (negative) dealer gamma. In the strike tooltip the subtraction is already baked into the displayed Put GEX: Net GEX at a strike = Call GEX + Put GEX exactly as shown — add the two numbers, don't subtract the put again. A negative (red) strike simply means the put leg dominates dealer hedging there; a positive (green) strike means the call leg dominates. ### What does ABS GEX tell me? ABS GEX is the sum of |CE GEX| + |PE GEX| across all strikes — total dealer hedging concentration regardless of side. High ABS GEX means a lot of gamma is in play; small spot moves trigger large hedging flows. Low ABS GEX means dealers can let the underlying drift without rebalancing. ### What is the Call Wall? The Call Wall is the strike with the heaviest call-side gamma exposure (max CE Gamma × CE OI) above spot. It typically acts as an upside ceiling because dealers who are short those calls have to sell into rallies that approach the wall, pushing price back. A rising Call Wall through the session is a bullish signal — dealers are stepping back from resistance. ### What is the Put Wall? The Put Wall is the strike with the heaviest put-side gamma exposure (max PE Gamma × PE OI) below spot. It tends to act as a downside floor because dealers short those puts buy into dips toward it. A falling Put Wall through the session is a bearish signal — dealers are abandoning support. ### Why are my GEX numbers different from SpotGamma or US GEX dashboards? We express GEX in crores (Rs ÷ 10⁷) and skip the US 100-contract multiplier. The formula and sign convention are the same as SpotGamma/Perfiliev; only the absolute magnitudes differ by a constant. Walls, regime direction, and proportional bar heights are identical to international tools. ### How does the strike-range filter work? Choose All to see every strike in the option chain. 5 / 10 / 20 narrows the chart to ATM ± N strikes — useful for focusing on the active zone. The KPIs (Net GEX, ABS GEX, Call Wall, Put Wall) always compute on the full strike list regardless of the visible range, so filtering never distorts the headline numbers. ### Why does Gamma Exposure look like zero on expiry day at close? At expiry close, options have no time value left — IV → 0 and gamma → 0 in the Black-Scholes formula. The data correctly reads zero. Use the time slider to scrub back to mid-session (e.g. 14:00) to see meaningful gamma before settlement. ### Live vs historical mode — what's the difference? Live mode pulls the latest minute snapshot and auto-refreshes via a countdown. Historical mode lets you pick any past trading date and replay that day's gamma exposure minute-by-minute via the time slider. Same chart, same metrics, different data source. ## How to read the Gamma Exposure chart 1. **Check the regime (Net GEX sign)** — Positive Net GEX = long-gamma regime (pinning/mean-reversion). Negative = short-gamma regime (trending). The colour of the Net GEX number tells you immediately. 2. **Identify the Call Wall and Put Wall** — Toggle Show Walls in settings. Call Wall is the upside ceiling, Put Wall is the downside floor. Spot tends to oscillate between them on positive-GEX sessions. 3. **Read the per-strike bars** — Green bars above zero are strikes where dealers stabilize price (positive Net GEX). Red bars below zero are strikes where dealers amplify moves. 4. **Use the ABS GEX line** — The blue overlay traces total gamma concentration. Spikes mark the most actionable strikes — where dealer hedging flows are largest. 5. **Scrub the time slider for context** — Drag the slider backward to see how walls migrated through the day. A rising Call Wall + rising spot = sustained bullish bias. A falling Put Wall + falling spot = breakdown risk. ## Related tools - [Open Interest](https://stockmojo.in/open-interest) — markdown: https://stockmojo.in/open-interest.md - [Multi-Strike OI](https://stockmojo.in/multistrike-oi) — markdown: https://stockmojo.in/multistrike-oi.md - [Max Pain](https://stockmojo.in/max-pain) — markdown: https://stockmojo.in/max-pain.md - [Put Call Ratio](https://stockmojo.in/put-call-ratio) — markdown: https://stockmojo.in/put-call-ratio.md ## Glossary Terms used: gamma-exposure, gex, call-wall, put-wall, dealer-hedging, open-interest. Definitions: https://stockmojo.in/glossary