Calendar Wiki

The College Calendar is a week-based calendar. It doesn't divide into months. Instead its dates are defined by the weekday, the year and the week. A period of six weeks is called a school period. A year spans 53 weeks which is 8 school periods and 5 weeks.

Year length[]

The year length is defined by Gregorian calendar rules.

Normal years have 365 days, which is one day more than 52 whole weeks. That means that the first day and the last day of the year fall on the same weekday. The following year starts one weekday later.

A leap year usually occur every 4 years and has one more day. From the College Calendar perspective, it is as if one year was skipped since the following year starts two weekdays later.

Week names[]

The first week of the year (which contains one to seven days) is called week zero. The week number increases but there is no week six, which is called week one-zero instead (one school period plus zero weeks). That convention was inspired by the Heximal Calendar system.

The sequence continues until the last week of the year (which contains one to seven days) called week eight-four.

Weeks of the year
School periods Week begins ends
0 zero Monday to Sunday Sunday
one Monday
1 one-zero Monday Sunday
8 eight-zero Monday Sunday
eight-four Monday to Sunday

Week zero length[]

Most of the time, week zero is not a full week: it loses some days to week eight-four of the previous year.

However week zero is a full week when the year starts on Monday. This would happen every seventh year if there were no leap years. With leap years, that is every sixth year except if there are two leap years in these six years. That could be either:

  • A leap year starting on Monday. There is another leap year after four years, which makes the interval five years instead of six.
  • A leap year following a year starting on Monday. That makes the leap year after that start on Sunday and end on Monday, which means the next year is directly a Tuesday-starting year. Due to the skipped Monday-starting year the interval becomes eleven years.

In this century, year 2001 had a full week zero, then the pattern is:

six, eleven, six and five years

That pattern repeats every 28 years until the end of the century, after which a leap year is skipped.

The importance of that pattern is that when week zero is a full week, week zero and previous year week eight-four are separate.

Notable days in 2024[]

Year 2024 dates (leap year)
day week name
Monday zero New Year's Day
Wednesday one-five Spring Equinox (North)
Sunday two-zero Easter
Thursday four-zero Summer Solstice (North)
Sunday six-one Autumn Equinox (North)
Thursday seven-five Thanksgiving
Saturday eight-two Winter Solstice (North)
Wednesday eight-three Christmas
Tuesday eight-four New Year's Eve



  • Months are gone
  • Day numbers themselves are gone!
  • Main concept to learn is the week day, which is easy enough
  • The progression of time through the year is embedded in the week name
  • Aligned with the week, which is what rules human routine
  • Year can easily be divided in three parts of three school periods each


  • No fixed date for important festive days
  • When you do need to know the number of days, counting in sevens is not that simple
  • No simple division of the year in four or twelve parts

See also[]