It would be easier to explain the inputs with an example. So let's assume, we want to price a 2-year maturity, 2,500 strike call option on a non-divided paying stock, which has a current price of 2,500, and implied volatility of 30% (0.30). Let the risk free discount rate be 5%(0.05). Then the inputs will be entered as follows:

Stock Price | 2,500.00 |

Strike Price | 2,500.00 |

Volatility | 0.30 |

Discount Rate | 0.05 |

Dividend Yield | 0.0 |

Maturity (years) | 2.0 |

Option Type | Call |

The above shows that the inputs are relatively straightforward. A few things that might cause some confusion are:

- The time to maturity is in years, so a maturity of 15 months will be inputted as 1.25 (=1.0+3/12).
- The volatility, discount rate, and dividend yield are not formated with %, e.g., 5% is entered as 0.05.
- Finally, the stock price, strike price, volatility, and maturity should be non-negative. If any of these is negative, it will be replaced with zero.