Close Zone™
SPXXL's proprietary projected closing price range for SPX, computed using session classification, gamma exposure, and intraday momentum.
The Close Zone™ is SPXXL's proprietary intraday price projection that estimates where SPX will settle at 4:00 PM ET. Unlike simple support/resistance levels, the Close Zone dynamically recalibrates throughout the session based on real-time data.
The Close Zone projection integrates:
- ●Current session classification and confidence
- ●Dealer gamma exposure at nearby strikes
- ●Intraday momentum and VWAP deviation
- ●Volume profile and value area migration
- ●Theta decay curves for nearby expirations
- ●Historical session-type close patterns
The Close Zone narrows as the session progresses — it's widest at 9:30 AM and tightest in the final hour. SPXXL's dashboard displays the projected range with confidence bands.
For 0DTE traders, the Close Zone is the core decision input: if your spread strikes are outside the Close Zone, time decay works for you. If price is approaching your short strike within the Close Zone, the engine signals to adjust or close.
The Close Zone becomes most actionable during the "Close Zone Phase" (3:30-4:00 PM ET) when theta acceleration reaches maximum velocity.
Related Terms
The rate at which an option loses value as time passes — accelerates dramatically for 0DTE options as expiration approaches.
The aggregate gamma positioning of options market makers — determines how dealer hedging amplifies or dampens SPX price moves.
A defined-risk options strategy that profits from directional movement — SPXXL's primary recommended structure for most session types.
Options that expire on the same day they are traded — the fastest-growing segment of the options market with unique risk/reward characteristics.