Last updated: July 18, 2026
zdte.ai's analytics are computed from a real-time SPX options chain sourced through professional-grade market data feeds during regular trading hours. Open interest, volume, and the Greeks (delta, gamma, theta, vega) used throughout the platform originate from data disseminated by the options exchanges themselves, not from a proprietary or self-reported source. zdte.ai does not observe individual traders' positions or intentions directly; every dealer-positioning figure described below is an estimate built from this exchange-disseminated data, not a measured fact.
Gamma exposure follows the standard convention used across the industry: for each listed strike and expiration, multiply the option's gamma by its open interest, by the square of the underlying's spot price, and by a scaling constant of 0.01, so the result estimates hedging flow for a one-percent move in the underlying (dollar notional expressions additionally include the 100-share contract multiplier; the charts on this site present these values as relative magnitudes for comparing strikes, not as exact dollar figures). That per-strike figure is then signed according to a dealer-side convention - the assumption, standard across the industry, that customer buy-to-open flow leaves dealers short that contract while customer sell-to-open flow leaves dealers long it - and summed across every strike and expiration on the chain.
This methodology and its assumptions are the same ones described in plain language on the gamma exposure guide and the gamma exposure glossary entry: the sign and the structure of the result (positive vs. negative, and where the concentrations sit) are considerably more reliable than any single precise dollar figure, because the calculation depends on an assumption about which side of each contract dealers hold. Different data providers make slightly different assumptions and will produce different exact numbers from the same underlying chain; that is expected, and is why zdte.ai treats GEX as a structural, directional read rather than a precise measurement.
Once gamma exposure is computed per strike, three recurring features of that profile are surfaced across the platform. The call wall is the strike above the current price carrying the heaviest concentration of call-side gamma exposure; operationally, dealer hedging concentrated there tends to slow advances into it, which is why it is read as a near-term ceiling. The put wall is its downside mirror: the strike below the current price with the heaviest put-side concentration, read as a level where hedging tends to cushion declines. The gamma flip (or zero-gamma level) is the estimated underlying price at which the aggregate, netted gamma exposure figure crosses from positive to negative - the boundary between a hedging regime that tends to dampen moves and one that tends to amplify them.
All three are estimates re-computed continuously from live open interest and are expected to shift as positioning changes, new expirations are listed, and existing contracts expire or roll. None of the three is a guaranteed support, resistance, or trigger level; they describe where hedging pressure is estimated to concentrate, not a price the underlying is bound to respect.
Figures update on a different cadence depending on account tier and market state:
Every figure described on this page is a structural estimate derived from public, exchange-disseminated options data under a stated set of assumptions, not a measurement of an actual dealer book and not a forecast of future price. zdte.ai publishes these analytics for informational and educational purposes only; they are not investment advice, and they are not a recommendation to buy, sell, or hold any security. See the full Investment Disclaimer for the complete risk statement, and the glossary for plain-language definitions of every term used on this page.