How to read this dashboard

This tool estimates options-based support/resistance structure for SPX from the free CBOE delayed options chain. Everything is recalculated from a fresh snapshot every 30 seconds. It is an educational market-structure tool — not financial advice.

What is GEX?

Gamma exposure (GEX) estimates how much option dealers must hedge as the underlying moves. Per contract:

GEX = gamma × open interest × 100 × spot² × 0.01

Calls count positive, puts negative (the standard dealer-positioning convention: dealers are assumed long calls / short puts). The result is dollars of hedging flow per 1% move in the underlying.

• Positive GEX (green) — dealers sell rallies and buy dips: volatility dampening, range/pin behavior.
• Negative GEX (red) — dealers buy rallies and sell dips: volatility amplification, faster directional moves.

GEX Heatmap

Rows are strikes (high → low), columns are the next 14 expirations, cell color is net GEX at that strike × expiration. The white dashed line marks spot. Scan around spot: big green above = potential resistance/pin, big green below = potential support; red clusters = unstable zones. The same-day column usually dominates intraday behavior.

Strike Map

The tornado chart shows call GEX (green, right) and put GEX (red, left) per strike for the selected expiration, with the net profile overlaid. Lines mark:

• Call Wall — strike with the largest positive net GEX (resistance / pin candidate).
• Put Wall — strike with the largest negative net GEX (support / acceleration zone if lost).
• Gamma Flip — estimated SPX price where aggregate GEX crosses zero after each contract's gamma is repriced across hypothetical spot prices. It separates modeled positive- and negative-gamma regions; the current regime card shows which side SPX occupies. It can be absent when exposure stays one-sided throughout the search range.

0DTE

Same-day expiration only, with a tighter ±3% strike window: 0DTE share of total volume, 0DTE net GEX, and the day's own walls/flip. SPX lists daily expirations; on non-trading days this tab shows the next expiry.

Option Flow

Call and put volume (or traded premium) by strike for the selected expiration, plus the largest contracts by premium. Side (buy/sell) is a heuristic — last trade at/above the ask counts as buying, at/below the bid as selling. A big flow number is not automatically bullish or bearish; combine it with the heatmap and strike map.

Sentiment

The page separates current directional pressure from the modeled volatility regime. These are market-state references, not statistically validated forecasts.

Reading	Components	Interpretation
Directional pressure	price change, put/call volume, delta tilt, put/call OI	bullish, mixed, or bearish current pressure
Volatility regime	distance to repriced gamma flip, VIX change, IV30 change, 25Δ skew	stable through high instability

Missing inputs are excluded rather than scored as zero. The page shows effective weights, input coverage, and confidence. Confidence measures data completeness only; it does not claim predictive accuracy. Even with complete inputs, confidence is capped at Medium because quotes are delayed, option volume is unsigned, and dealer positions are estimated.

A practical workflow

• Start with the closest expiration during the cash session.
• Check the next weekly expiration for larger walls.
• Compare spot with the largest positive and negative GEX strikes.
• Recheck after major moves or macro events — walls migrate intraday.

Data & limitations

• Quotes are CBOE delayed data (~15 minutes). The math is recomputed every 30 s on the latest snapshot.
• Open interest updates once each morning, so early-session OI can lag yesterday's trading.
• GEX assumes the standard dealer book (long calls, short puts); reality varies, so treat levels as zones, not lines.
• Always combine with price action, volume, liquidity, news and your own risk controls.