Bookkeepers, project managers, HR departments and more use the Excel Date & Time functions WEEKNUM, ISOWEEKNUM, WORKDAY, WORKDAY.INTL to calculate time. Here's how.

Excel has over 475 formulas in its Functions Library, but we've selected the most popular, from date and time functions to mathematics and simple data manipulation.

EOMONTH Start_date: A date that signifies the start date example, 1/22/2021. Do not enter the start date in the text; a problem will happen. The start_date is required.