Excel Formulas SUM: Adds up a range of cells. AVERAGE: Calculates the average of a range of cells. COUNT: Counts the number of cells in a range that contain data. IF: Performs a logical test and returns a different value based on the result. VLOOKUP: Looks up a value in a table and returns the corresponding value from another column. HLOOKUP: Looks up a value in a table and returns the corresponding value from another row. INDEX: Returns the value at a specified row and column in a range. MATCH: Finds the position of a value in a range. ROUND: Rounds a number to a specified number of decimal places. DATE: Converts a text string into a date value. * TIME: Converts a text string into a time value.