How Often Does the Calendar Repeat Itself?
The Gregorian calendar repeats itself in 28-year cycles. A calendar for a particular non-leap year repeats itself after 11 years twice and repeats itself after six years once in a 28-year span. Calendars for leap years repeat themselves every 28 years.
According to Time and Date, the calendar for 2014 will repeat itself in 2025, then in 2031, then in 2042, then in 2053, then in 2059 and so on. In other words, these future years are when the calendar will have the same number of days as 2014 and start on the same day of the week. Whereas the last leap year, 2012, will not repeat itself until 2040, then 2068; calendars in leap years only repeat themselves every 28 years.