An option premium calculator estimates the fair value of a call or put using the Black–Scholes model. Enter the spot price, strike, days to expiry, volatility and interest rate, and ATS instantly returns the theoretical premium plus the option Greeks — Delta, Gamma, Theta, Vega and Rho.
Enter spot, strike, days to expiry and volatility to compute the option fair value and Greeks.
An option premium is the price a buyer pays — and a seller (writer) receives — for an option contract. It is made up of intrinsic value (how far the option is in-the-money) plus time value (the chance the option moves further in-the-money before it expires). The ATS Option Premium Calculator estimates this premium for any call or put.
The calculator uses the Black–Scholes model, the industry-standard options pricing formula. From the spot price (CMP), strike price, days to expiry, volatility and the risk-free interest rate — with an optional dividend yield — it computes the theoretical fair value of the option, recalculating live as you change any input.
Alongside the premium it shows the option Greeks. The Greeks tell you how sensitive the premium is to the underlying price (Delta), the rate of change of Delta (Gamma), the passage of time (Theta), volatility (Vega) and interest rates (Rho) — the key levers behind every options trade.
| Greek | Measures | Read it as |
|---|---|---|
| Delta | Premium sensitivity to a ₹1 move in the underlying | ≈ rupees gained/lost per ₹1 move (0 to 1 for calls, −1 to 0 for puts) |
| Gamma | Rate of change of Delta | How fast Delta shifts as the spot price moves |
| Theta | Time decay per day | Rupees of premium lost each day, all else equal |
| Vega | Sensitivity to a 1% change in volatility | Premium change for each 1% move in implied volatility |
| Rho | Sensitivity to a 1% change in interest rates | Premium change for each 1% move in the risk-free rate |
It uses the Black–Scholes model, the standard options pricing formula. From the spot price, strike, days to expiry, volatility and the risk-free interest rate it computes the theoretical (fair) premium for a call or a put, updating instantly as you edit inputs.
The Greeks measure how the premium reacts to different factors: Delta (underlying price), Gamma (rate of change of Delta), Theta (time decay), Vega (volatility) and Rho (interest rates). The calculator shows all five alongside the fair value.
Black–Scholes gives a theoretical value from the inputs you enter. The market premium also reflects supply and demand, the implied volatility traders are actually pricing in, dividends and liquidity — so the two can differ. Adjust the volatility input to match current market conditions.
Volatility is the biggest driver of time value. Higher volatility raises the premium for both calls and puts because there is a greater chance the option ends deeper in-the-money. This sensitivity is measured by Vega.
Yes. Choose Call or Put and the calculator applies the correct Black–Scholes formula and Greeks for that option type.