Gamma exposure (GEX) is a way to estimate how options dealers may have to trade the underlying as price moves. For 0DTE traders, it is a context tool — it describes the conditions you are trading into. It is not a signal, a prediction, or a reason to trade.

What dealer gamma means

When dealers are net long gamma, hedging tends to lean against price moves (buy dips, sell rips), which can dampen intraday volatility. When dealers are net short gamma, hedging can amplify moves (sell weakness, buy strength), which can make ranges expand quickly. Same-day expiration concentrates this effect because gamma is largest near the money close to expiration.

The gamma flip point

The "zero-gamma" or flip level is the modeled price where aggregate dealer gamma crosses from positive to negative. Above it, conditions tend to stabilize; below it, they tend to destabilize. It is a modeled level that drifts through the day — treat it as a moving reference, not a fixed line of support or resistance.

How disciplined traders use GEX

• As context for whether to expect mean-reversion (long-gamma regime) or trend/expansion (short-gamma regime).
• Alongside price structure — VWAP, the opening range, prior-day high/low — never on its own.
• To inform defined-risk structure choices, not to size up or chase.

Risk notes

GEX is a model built on public data and assumptions about dealer positioning; the real positioning is never fully observable. It does not tell you direction, and it does not reduce the risk that a 0DTE option can lose its value the same day. Always define max loss before entry.