What is gamma exposure (GEX)?

The hidden force that makes some days quiet and others explosive.

Gamma exposure (GEX) measures how much options dealers must buy or sell to stay hedged as the stock moves. It is one of the most useful lenses for understanding why a market is calm, choppy, or prone to violent moves on a given day.

The core idea

When you buy an option, someone (a dealer / market maker) sells it to you. To avoid taking a directional bet, the dealer hedges by trading the underlying stock. As the stock moves, that hedge has to be adjusted — and the direction of those adjustments is what GEX captures. Millions of contracts of hedging flow adds up to real pressure on price.

Why you should care

GEX does not tell you which way price goes. It tells you the character of the tape — whether moves are likely to be dampened and mean-reverting, or amplified and trending. That context changes how you size and time every trade.

Where to see it

Obelion's GEX view plots dealer gamma by strike for any ticker, with the key levels and the gamma-flip point marked. This track explains how to read it, from the ground up.

Gamma exposure by ticker

How these numbers are computed, including sources, formulas and limitations, is documented on the methodology page.

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