How many days in a millennium? The calendar system that was in use during a particular millennium determines the actual number of days that elapse during that time span.
* The First Millennium (1 - 1000 AD) consisted of 365,250 days.
* The Second Millennium (1001 - 2000 AD) consisted of 365,237 days.
* Our current Millennium (2001 - 3000 AD) will consist of 365,242 days.
Warmie
