GEX Heatmap by Expiry: How to Read the Strike × Expiration Matrix

Reading the Interface

Before diving into interpretation, here is what each part of the screen shows:

Concentration Badges (0DTE / This Week / Month+)

The three pills at the top left tell you where gamma is concentrated by time — expressed as a percentage of the total absolute GEX across all expirations.

• 0DTE % — how much of today's total gamma expires today. When this is 30%+ it means a large portion of dealer hedging pressure dissolves at 4PM. High 0DTE environments create strong intraday pinning at nearby strikes but the structure can move sharply after close once that gamma rolls off.
• This Week % — gamma expiring between tomorrow and this Friday. Combined with 0DTE, this tells you how much of the current structure is a this-week problem vs a multi-week structural feature.
• Month+ % — everything further out. High Month+ means the current structure is driven by longer-dated positions — walls built here are durable and move slowly.

The three percentages always sum to 100%. A reading of 0DTE 60% / Week 30% / Month 10% means the market is almost entirely driven by today's expiration — expect strong pinning behavior but also a structural vacuum after close. A reading of 0DTE 10% / Week 20% / Month 70% means the structure is driven by longer-dated positions and will be stable across sessions.

The 2D Matrix (Strikes × Expiry)

The main grid: each row is a strike price, each column is an expiration date. The cell at the intersection shows the net GEX at that exact coordinate — that specific strike, on that specific expiry.

• Green cell = call-dominant GEX at that strike/expiry (dealers long gamma — pinning behavior)
• Red cell = put-dominant GEX (dealers short gamma — amplifying behavior)
• Darker/brighter color = larger GEX magnitude at that cell
• Empty cell = no meaningful GEX at that coordinate

Click any cell to see the exact strike, expiration date, GEX amount, and whether calls or puts dominate there.

Row Totals Column

The rightmost column labeled Total sums all expiration cells for each strike. This number is the same GEX value shown for that strike in the GEX Profile chart — the aggregate across all expirations. The heatmap lets you see exactly which expirations make up that total.

Right Panel — Net by Expiry

The mini bar chart on the far right shows one bar per expiration date, top to bottom in the same order as the columns. Each bar's length represents the net GEX summed across all strikes for that expiration. This answers: which expiration date has the most gamma weight today?

The 0DTE bar (today's expiry) is always shown at full opacity. All other bars are slightly dimmed. When the 0DTE bar is the longest, today's contracts are driving the structure. When a weekly or monthly bar is longest, the structural pressure comes from a future date — and will persist past today's close.

What is the GEX Heatmap?

The GEX Profile chart collapses all expirations into a single bar per strike — you see the aggregate gamma at $670, but you cannot see whether that gamma is coming from today's 0DTE contracts, this week's Friday expiry, or the monthly OPEX. The heatmap separates them.

The heatmap is a matrix: strikes on one axis, expiration dates on the other. Each cell shows the net GEX contribution from options at that specific strike AND that specific expiration. At a glance, you can see the entire structure decomposed by time — which expirations are building the walls, which are adding or subtracting from each level, and where multiple expirations reinforce or conflict with each other.

This reveals the time-dimension of GEX structure that the profile chart flattens. The question "is this a real wall or a temporary one?" is answered by the heatmap: if the wall is backed by only this Friday's contracts, it's temporary. If it's backed by three consecutive weekly expirations and the monthly, it's durable.

Reading the Color Scale

The heatmap uses a diverging color scale centered on zero:

• Bright green cell — strong positive GEX at that strike/expiry. Call gamma is dominant. Dealers are net long gamma at that specific strike for that expiration date. They will buy dips near that level into that expiration's close.
• Bright red cell — strong negative GEX at that strike/expiry. Put gamma is dominant. Dealers are net short gamma there — moves through this zone for that expiry will be amplified rather than dampened.
• White or near-white cell — minimal GEX at that strike/expiry. Little to no gamma concentration there — neither call nor put writers are concentrated at this exact strike for this exact expiration.

The color intensity corresponds directly to magnitude. A bright green cell at $670 for the Friday expiry means call writers at $670 expiring Friday are contributing significant positive gamma — dealers are long gamma there and will actively buy dips near that level into Friday's close. The brighter the color, the stronger the structural significance of that specific cell.

Identifying Hot Zones

The brightest cells on the heatmap are the most structurally significant strike/expiry combinations — the coordinates where the most gamma is concentrated at a specific expiration. These hot zones are the highest-conviction structural levels because they represent maximum dealer hedging obligation at a precise time coordinate.

Durable hot zones: A bright green cluster at $675 across three consecutive weekly expirations means this is a multi-week Call Wall. It will persist as a structural ceiling until those contracts expire or are actively closed. Institutions with significant $675 call positions across multiple expirations will defend that level aggressively — selling into rallies at $675 repeatedly until their contracts expire.

Temporary hot zones: A bright red cluster at $660 only for today's expiry is a 0DTE put wall. It matters significantly today — creating a floor that dealers will defend through the session — but it disappears entirely at 4PM when those contracts expire. A trade using this level as support needs to account for the fact that the structural basis for that support ceases to exist at close.

Expiration Clustering

When multiple expirations show the same color at the same strike, the structural level is reinforced across timeframes. This multi-expiry clustering creates the strongest possible GEX walls — levels where dealer hedging obligation is not just large today, but large this week and this month.

Aligned clustering (same color, multiple expirations): The structural level is backed by positions at different timeframes. Writers at different expirations all need the same hedging behavior from dealers. The combined hedging pressure from all these positions creates an extremely strong wall that requires significantly more buying pressure to break than a single-expiry wall would.

Conflicting clustering (different colors at same strike): When expirations show opposite colors at the same strike — for example, green on 0DTE but red on the weekly — the two timeframes are pulling in opposite directions. This structural tension has a predictable effect: expect more volatile behavior at that level. The market is contested here between different groups of options writers with opposing exposures. As the shorter expiry resolves, the conflict resolves too — and the move that follows can be sharp because the constraint disappears abruptly.

Heatmap vs GEX Profile

The two charts serve complementary purposes — use each for what it's best at:

GEX Profile: Aggregate view with all expirations summed. Best for: the current structural snapshot, identifying the dominant Call Wall and Put Wall, understanding today's net regime, and quick context checks. The profile is faster to read but hides the time structure.

GEX Heatmap: Decomposed view, expiry by expiry. Best for four specific use cases:

1. Diagnosing which expiry is driving a level — when the profile shows a wall at $670, the heatmap tells you which expirations are building it. 0DTE? Weekly? Monthly? This tells you how long the wall will last.
2. Identifying upcoming expiration events that will shift structure — you can see which expirations are carrying significant gamma and when they expire. Major expiration events (especially OPEX) will significantly reshape the profile chart as those contracts roll off. The heatmap lets you anticipate those structural shifts in advance.
3. Spotting multi-expiry confluence zones — the highest-conviction levels in the current structure are where the heatmap shows consistent bright colors across multiple expirations at the same strike. These are your anchor levels for the week or month.
4. Planning for wall migration — as expirations roll off, watch how the heatmap changes. A wall that was at $675 across four expirations will shift when the two nearest expirations expire, potentially moving the effective wall to a different strike. The heatmap shows you this migration before it happens.