Adding 21 days to a date

Am I looking in the right place?

I want to add a page to a site which allows the user to enter a date, and the page works out a simple timetable for the user. ie date entered + 21 days you need to do this, date + 25 days you need to do that.

Is there any simple scrip for this?

I have looked at Active X and can can write code to achive the desired results, but is this the best way forward? Are people staying away from this because of viruses? Is it netscape compatable (I think not)?

Should I be looking to do this another way?

Any pointer would be much appreciated.

Are you using VBscript? If so try the dateadd function,

newdate = dateadd("d", 21, mydate)