Gamma Exposure (GEX)
A measure of how much option dealers must trade to stay hedged as the market moves.
Definition
Gamma exposure (GEX) aggregates the gamma of every open option contract to estimate how option market-makers will need to rehedge as the underlying moves. Because dealers hedge their option books in the underlying, their collective gamma position shapes how price tends to behave around key strikes.
Why it matters
When dealers are net long gamma (positive GEX), they sell into rallies and buy into dips to stay delta-neutral, which dampens volatility and pins price. When they are net short gamma (negative GEX), they must buy higher and sell lower, amplifying trends and widening intraday ranges. Knowing the regime helps you anticipate whether a session is likely to be choppy and range-bound or trend-prone.
Example
Suppose Nifty sits at 22,000 and dealers are heavily long gamma around that strike. As Nifty drifts up to 22,050, dealers sell futures to rehedge, pulling price back. The same happens on the downside, so the index keeps gravitating toward 22,000 — a classic positive-gamma pinning effect into expiry.
See it live
TradePulse maps gamma across strikes on the live Nifty option chain so you can spot the dealer-hedging zones.