How to create a Date Countdown in Excel to show you both the number of calendar days remaining until an event date, as well as how to calculate the number of working days left between now and that particular date. If you need to count "days left" or "days to go" to a particular date, you can achieve this in a way that will automatically update whenever you open the workbook by using the TODAY() function in Excel. You can also countdown the number of working days to an event date that will exclude weekends using the NETWORKDAYS function in Excel. In this video, we create a date countdown to a software implementation project go-live date.