Option Greeks Calculator
Pick an underlying (the live spot price loads automatically), set a strike, expiry, and implied volatility, and see the Black-Scholes theoretical price plus Delta, Gamma, Theta, Vega, and Rho for both the call and the put.
Inputs
What Delta and Gamma tell you
- Delta is roughly how much the option's price moves for a 1-point move in the underlying. A call Delta of 0.50 means the premium moves about 0.50 for each 1-point move. Call Delta runs from 0 to 1, put Delta from −1 to 0.
- Gamma is how fast Delta itself changes as the underlying moves. It is highest for at-the-money options close to expiry, which is why those options' Delta can swing sharply on small price moves. The Gamma chart above peaks near the strike for that reason.
- Theta is the estimated change in premium per day from time passing alone, all else equal. Vega is the change for a 1-point change in implied volatility. Rho is the change for a 1-point change in interest rates.
More background: Options basics and margin and leverage.
Model limits: Black-Scholes assumes European-style exercise, constant volatility, and no dividends. Real option premiums depend on the implied volatility the market is actually pricing, which this tool does not fetch — you enter it. Results are theoretical estimates for learning, not trade recommendations.