If you use Excel to project manage then you will know that most people work a five day week – Monday to Friday (if they are lucky).  So if you have a project start date and the number of days it will take to complete then if you just added the number of days to the start date, it would not take into account the weekend days in your project.

By using the =WORKDAY() formula allows you to specify a beginning date, the number of workdays until the end of the project.

An example.

My VBA project has a start date of 01 July 2013 and I know it will take 56 days of resources.

So, as you can see below I have entered into cell C5 the formula =WORKDAY(C3,C4) which calculates 56 workdays or Monday though Fridays for 56 days.

Excel has therefore calculated  my estimated finish date which is 17 September 2013- EASY!