You can use the Volatility Calculator to:

- Calculate an option's
**Implied Vol**based on its**Theoretical Value**(price). - Calculate an option's
**Theoretical Value**(price) based on its**Implied Vol**.

**Note**: The futures price in the **Underlying Price** field is required for both calculations.

To use the Volatility Calculator:

Right-click the options instrument and select

**Open**|**Open Vol Calculator**from the context menu.For example, right-click the

**CBid**column at the 2765 strike in the Options Chain.The Volatility Calculator opens seeded with the LTP of the underlying in the

**Underlying Price**field.**Tip**: The Volatility Calculator can also be opened from the Market Grid, Order Book, Fills, and MD Trader widgets.Enter an option price in the

**Theoretical Value**field.The option instrument's implied volatility is calculated and displayed in the

**Implied Vol**field.Enter a value in the

**Implied Vol**field.The option instrument's price is calculated and displayed in the

**Theoretical Value**field.If needed, enter a new value in the

**Underlying Price**field to recalculate the Implied Vol and Theoretical Value for the options instrument.**Tip**: You can also click the Market Explorer in the calculator to select a different options instrument. When selected, the instrument's underlying price is displayed.