Gamma Exposure (GEX)
Aggregate dealer gamma across the option chain, used to read whether hedging damps or amplifies moves.
Gamma exposure aggregates how much dealers must re-hedge as spot moves, summed across the option chain. When dealers are net long gamma they hedge against the move, selling strength and buying weakness, which tends to compress realized volatility. When they are net short gamma they hedge with the move, which tends to amplify it. The zero-gamma level is the spot price where the aggregate flips sign, which is why it gets watched as a regime boundary rather than a target. Two cautions specific to crypto: dealer positioning is inferred from open interest, not disclosed, so every GEX number is a model; and the crypto options market is far smaller than the equity one, so its influence on spot is correspondingly smaller. We compute ours from the daily open-interest chains of five venues, Deribit, Bybit, Binance, OKX and Delta Exchange, summed or one venue at a time.