GEX Heatmap

What is a GEX Heatmap?

A GEX (Gamma Exposure) Heatmap is a visualization tool that displays net gamma exposure across multiple strike prices and expiration dates in a color-coded grid. Each cell in the heatmap represents the net gamma at a specific strike for a specific expiration. Green cells indicate positive gamma (call-dominated strikes), while purple or red cells indicate negative gamma (put-dominated strikes). The color intensity reflects the magnitude of gamma at that point.

Unlike a standard GEX chart that aggregates all expirations into a single view, the heatmap breaks down gamma exposure per expiration, revealing how the options landscape evolves over time. This makes it easier to spot where specific expirations contribute the most gamma, and how the call wall, put wall, and gamma flip zones shift as you look further out in time.

How to Read the Gamma Exposure Heatmap

The heatmap table has strike prices on the vertical axis and expiration dates along the top. Here is how to interpret the data:

• Green cells: Positive net gamma — call gamma exceeds put gamma at that strike/expiration. These strikes act as “magnets” that attract and stabilize price.
• Purple/red cells: Negative net gamma — put gamma exceeds call gamma. These strikes can amplify price moves as market makers hedge in the same direction as price.
• Key Levels sidebar: Shows the aggregated call wall, put wall, and gamma inflection point across all displayed expirations.
• Net GEX by Expiry: Displays total net gamma for each expiration, showing which dates contribute the most hedging pressure.

The strongest color intensities indicate the most important gamma levels. Look for clusters of intense green above the current price (resistance) and clusters of intense purple below (support).

Understanding Call Walls and Put Walls

Call walls and put walls are the strike prices where market makers hold the most gamma exposure. These levels are critical for understanding intraday price dynamics:

• Call Wall: The strike with the highest positive gamma exposure. As the stock approaches this level, market makers who are long gamma will sell shares to hedge, creating resistance. This typically acts as a price ceiling in positive gamma environments.
• Put Wall: The strike with the most negative gamma exposure. As price drops toward this level, market makers buy shares to hedge, creating support. This acts as a price floor.
• Gamma Flip: The price level where total gamma transitions from positive to negative. Above this point, market makers dampen moves. Below it, they amplify moves. This is the volatility regime boundary.

The heatmap allows you to see which expirations contribute most to these key levels, helping you understand how persistent or temporary the support and resistance zones may be.

Frequently Asked Questions