EMA 50SMA 20SMA 10
GEX by Strike
GEX Profile by Price
Net GEX if the index moved to each price
All expiriesEx next weekEx next monthly
At the October 28, 2026 close, SPX finished at 7,744 (+0.28%). Net dealer gamma exposure across all expiries was $32.2B per 1% move, up from $19.1B the session before and higher than 59% of the past year's sessions. The index closed 36 points (0.5%) above its 7,708 gamma flip, where dealer hedging tends to lean against moves rather than chase them. The call wall is 8,000 (+3.31% from spot) and the put wall 7,000 (−9.61%). Contracts expiring within 7 days carry $7.8B of the total, about 24%.
| Close | 7,744 (+0.28%) |
|---|---|
| Net GEX · all expiries | $32.2B (prior $19.1B) |
| Net GEX · within 7 days | $7.8B |
| Net GEX · within 30 days | $3.5B |
| Gamma flip · all / 7d / 30d | 7,708 / 7,729 / 7,739 |
| Call wall / put wall · all | 8,000 / 7,000 |
| Call wall / put wall · 30d | 8,000 / 7,700 |
| Net GEX percentile, 1 year | 59th |
Over the past 253 sessions, SPX closed with negative net gamma on 35% of days and below its gamma flip on 36%; the median net GEX was $20.9B. The current positive-gamma run is 2 sessions long. Over the last 60 sessions the call wall sat at 8,000 on 60 days and the put wall at 7,000 on 42.
End-of-day values from the GEX history for the S&P 500 (SPX), computed from closing option chains; the live chart above updates through the session, so its figures can differ. For the full post-close write-up, read the Daily Market Review for October 28, 2026.
This chart estimates options dealer gamma exposure for S&P 500 index (SPX) options, the most actively traded index options in the world and the center of 0DTE trading. Because SPX dealers hedge with S&P 500 futures (ES) and SPY, SPX GEX is the most widely watched gauge of whether hedging flows are likely to dampen or amplify moves in US stocks. Pick an expiry to isolate 0DTE or a single expiration, or switch index below.
Strike-level GEX uses each contract's open interest and gamma, assuming dealers are long calls and short puts. The GEX profile reprices gamma with Black-Scholes at 60 prices within ±20% of spot (±30% for VIX), using each expiry's implied interest rate and dividend yield solved from put-call parity and measuring volatility time in trading days (business days ÷ 262, with same-day expiries counted as one day). The implied rates and dividends by expiry are listed on the volatility surface page.
Gamma exposure estimates how much options dealers would need to buy or sell in the underlying to stay delta-hedged when the price moves. For each strike it multiplies option gamma by open interest, the contract multiplier and the squared index level, and expresses the result in dollars per 1% move. Summing across strikes gives total net GEX.
Positive GEX means dealers are estimated to be long gamma: they sell into rallies and buy into dips to stay hedged, which tends to dampen moves and lower realized volatility. Negative GEX means dealers are short gamma and hedge in the same direction as the move, buying strength and selling weakness, which can amplify moves and raise volatility.
The gamma flip is the price at which total net GEX changes sign. Above it the market is estimated to be in a positive gamma regime, below it in a negative gamma regime. On this site it is the lowest price at which the all-expiries GEX profile crosses zero.
The call wall is the strike with the largest call gamma and the put wall is the strike with the largest put gamma. Because dealer hedging is concentrated around these strikes, they are often described as resistance (call wall) and support (put wall), especially as expiration approaches. They are estimates of where hedging flows cluster, not forecasts of price, although they move as positions change and are not guaranteed levels.
The chart updates each time you load the page. Reload the page to get the latest values during the session. Before the open, at night and on weekends it shows the last session's chain. Open interest is published once a day, so switch to Volume GEX to see positioning built up today, such as 0DTE trading.
GEX depends on assumptions: which side dealers are on, whether open interest or volume is used, which expirations are included, how gamma is computed and with what rates, dividends and time to expiry. This site assumes dealers are long calls and short puts, uses Cboe gamma for the strike chart, and reprices gamma with implied rates and dividends for the profile. Different choices shift totals and levels, so compare levels within one source over time.
No. GEX describes a likely hedging backdrop, not a forecast. The dealer-positioning assumption can be wrong, for example when customers sell puts or buy calls in size, and macro news can overwhelm hedging flows. Use it as context alongside price, volatility and the VIX term structure. Nothing on this site is investment advice.
Data is delayed and may be incomplete. Nothing here is investment advice.