Although there are many, many more that you'll find useful when building models, here's a list of the most basic functions that you can't be without.

Function |
What It Does |

SUM | Adds up, or sums together, a range of cells. |

MIN | Calculates the minimum value of a range of cells. |

MAX | Calculates the maximum value of a range of cells. |

AVERAGE | Calculates the average value of a range of cells. |

ROUND | Rounds a single number to the nearest specified value, usually to a whole number. |

ROUNDUP | Rounds up a single number to the nearest specified value, usually to a whole number. |

ROUNDDOWN | Rounds down a single number to the nearest specified value, usually to a whole number. |

IF | Returns a specified value only if a single condition has been met. |

IFS | Returns a specified value if complex conditions have been met. |

COUNTIF | Counts the number of values in a range that meet a certain single criterion. |

COUNTIFS | Counts the number of values in a range that meet multiple criteria. |

SUMIF | Sums the values in a range that meet a certain single criterion. |

SUMIFS | Sums the values in a range that meet multiple criteria. |

VLOOKUP | Looks up a range and returns the first corresponding value in a vertical table that matches exactly the specified input. |

HLOOKUP | Looks up a range and returns the first corresponding value in a horizontal table that matches exactly the specified input. An error is returned if it cannot find the exact match. |

INDEX | Works like the coordinates of a map and returns a single value based on the column and row numbers you input into the function fields. |

MATCH | Returns the position of a value in a column or a row. Modelers often combine MATCH with the INDEX function to create a lookup function, which is far more robust and flexible and uses less memory than the VLOOKUP or HLOOKUP. |

PMT | Calculates the total annual payment of a loan. |

IPMT | Calculates the interest component of a loan. |

PPMT | Calculates the principal component of a loan. |

NPV | Takes into account the time value of money by giving the net present value of future cash flows in today's dollars, based on the investment amount and discount rate. |

There's a lot more to being a good financial modeler than simply knowing lots of Excel functions. A skilled modeler can select which function is best to use in which situation. Usually, you can find several different ways to achieve the same result, but the best option is always the function or solution that is the simplest, clearest, and easiest for others to understand.