Cala TerminalGEX in plain language
Listed options have gamma: how fast delta changes as the underlying moves. Market makers who are short customer options often hedge by trading the underlying. When many contracts sit near a strike, that hedging can add buying as the market falls and selling as it rises — or the reverse — depending on the sign of dealer gamma.
GEX (gamma exposure) packages that idea into a chart: an estimated view of dealer gamma positioning, with an explainer of what positive and negative gamma environments mean for volatility. Cala computes and displays this as structure — not as a trade ticket.
Dealers, gamma, and why spot can feel “pinned” or volatile near levels
In a simplified story, positive dealer gamma is associated with hedging that can dampen moves (spot can feel “sticky” or pinned near large open-interest strikes). Negative dealer gamma is associated with hedging that can amplify moves (spot can feel jumpy). That is a classroom sketch of inventory hedging — not a guarantee that dealers are positioned that way today, and not a P&L forecast for anyone.
Levels on a GEX chart are strikes where modeled exposure is large. Price can ignore them. Expiry, spot jumps, and new flow rewrite the map. Cala does not claim to predict dealer hedges perfectly.
GEX vs max pain vs open interest by strike
Use the three together as a map of where options mass sits. Do not collapse them into one “the market must go here” rule. Max pain is not a magnet you are owed; GEX is not a buy or sell signal.
Model of dealer gamma by strike — a volatility-structure lens. Estimate from open interest, not a live inventory feed.
The strike where the most options would expire worthless, computed per expiration — a widely discussed options concept, shown for context.
Raw positioning: how many contracts are open at each strike. GEX is derived from that kind of data; OI is the inventory count, not the hedge story.
How to use GEX as context, not a trade ticket
Reasonable research questions: “Where is modeled dealer gamma concentrated relative to spot?” “Did GEX flip sign after a large move?” “Does that sit next to unusual options or dark pool prints today?” Unreasonable: “GEX says buy here,” “dealers must defend this strike,” or any implied win rate.
Pair GEX with dark pool prints and options flow the same way you pair a map with a weather report — additional description, not an order.
Where Cala surfaces GEX
Cala displays dealer GEX by strike alongside options max pain and open interest so you can see options-market structure at a glance. The same structure section covers unusual options / sweeps and dark pool. Informational data from a third-party feed; US-only; may be delayed.
Gamma exposure and max pain are listed on Pro (7-day trial, then web $39.99/mo or $349.99/yr). Free plan: no credit card, daily limits. Deep Mode lets you watch multi-step analysis live if you want the AI to narrate the structure — still not a recommendation.
Caveats: model assumptions, delays, US options
GEX depends on assumptions (whose gamma, which options, how dealers are modeled). Vendors differ. Data may be delayed. Coverage is US options. A model will not capture every exotic, every customer, or every hedge overlay.
Informational and educational only. Not investment advice, not a trade signal, and not a recommendation. Market data may be delayed. Cala is not a broker and does not execute trades.
FAQ
Is GEX a buy or sell signal?
No. GEX is an estimate of dealer hedging context. Cala does not use it as a recommendation, prediction, or trade ticket.
What’s the difference between GEX and max pain?
GEX estimates dealer gamma by strike (a volatility-structure model). Max pain is the strike where the most options would expire worthless for a given expiration. Both are shown for context; neither is a forecast.
Does Cala include GEX on Free or Pro?
Gamma exposure and max pain are marketed on Pro (7-day trial, then billed). Free is no card with daily limits. Check the web app for what your account can open today.
Is GEX real-time?
Treat it as possibly delayed. Cala’s structure data comes from a third-party provider and may lag. It is not a live tape of dealer hedges.
GEX vs “unusual options” — how do they relate?
Unusual options / sweeps are individual (or screened) options prints: strike, expiry, side, premium. GEX is a modeled snapshot of dealer gamma from open interest. Related desks, different objects — complementary context, not a combined signal.
Open GEX in Cala
Start free on the web (no card) or continue to Pro after a 7-day trial. GEX is structure context — not a signal.
Open GEX in Cala