Excel’s Date & Time functions ease the workload for bookkeepers, project planners, HR departments, and other jobs where time is money. The four functions covered here—ISOWEEKNUM, WEEKNUM ...

All businesses need to calculate dates and times for payroll, expenses, inventory and more. We show how Excel turns dates into serial numbers for easier calculations, and we discuss Networkdays ...

By default, Excel for the PC uses the 1900 date system, while its Mac counterpart uses the 1904 date system. In most cases, users won't notice this subtle difference.

If Microsoft Excel does not recognize dates, then there is something wrong with the formatting. Use any of the methods mentioned here to format cells perfectly.

A TechRepublic member wrote for advice on calculating the years, months, and days elapsed between two dates. This tutorial explains the solution provided by TechRepublic contributor Jeff Davis.