https://www.barchart.com/etfs-funds/quotes/SPY/gamma-exposure?expiration=2025-10-30-w
  Gamma Exposure (GEX) also known as Gamma Levels, measures the change in 
delta exposure for options based on changes in the underlying price. 
Gamma exposure highlights important price levels where there is 
significant gamma based on market positioning and open interest. 
These 
elevated values reflect where market-makers may need to hedge to 
mitigate their risk, offering important levels of support and 
resistance. By default, gamma exposure levels are calculated on 4 nearby
 expirations, based on a 1% move of the underlying security using gamma 
and open interest. 
Gamma exposure is calculated and updated throughout 
the day. Current gamma values, volume, and open interest can be found in
 the Volatilities & Greeks page for the security. For more 
information, watch this YouTube video.

 
