I don't know of a way w/o Date::Calc, however depending on what you are doing you may not need perl. If you are doing something as simple as taking the users local time and displaying a msg like good morning, good afternoon, good evening, etc. That is better left to stuff like Javascript. However if it's not (which i suspect it isn't) as simple as that then i'm inclined to ask why you can't install Date::Calc? just restrictions or not wanting to fool with it?