Calendar Years That Match 2025. To find years with calendars identical to 2025, we need to account for this irregularity. The first year recorded by this calendar is 1583, the first full year of the gregorian calendar.

The first year recorded by this calendar is 1583, the first full year of the gregorian calendar. Since 1st january of any given year occurs on one of seven weekdays, and a year is either a leap year or not, there are fourteen possible calendar years.