Delta Explainer
Delta estimates the change in an option’s theoretical value for a small change in the underlying price, with other inputs held constant. Long calls normally have positive delta, while long puts have negative delta because their values tend to move in opposite directions.
An equity call with a delta of 0.60 might gain about $0.60 per share for a $1 rise at that moment. Because a standard contract generally covers 100 shares, the position’s dollar exposure must include the multiplier and number of contracts.
Traders use delta as a hedge ratio and sometimes as a rough probability shorthand, but those interpretations are approximations. Delta changes with the underlying, time, and volatility. Deep in-the-money options approach stock-like exposure, while far out-of-the-money options tend toward zero.
Portfolio delta can summarize directional sensitivity across shares and option legs, yet a delta-neutral position is only neutral for a small move at one instant. Gamma, jumps, spreads, and simultaneous volatility changes can make realized gains and losses differ sharply from the estimate.
Delta estimates a small-move response with other inputs fixed.
Calls and puts usually carry opposite signs.
Per-share delta must be multiplied by covered units and contracts.
The headline decimal is not the whole dollar exposure.
Price, time, and volatility reshape it continuously.
A neutral hedge requires monitoring and rebalancing.
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