The time that unites us
Time is the only wealth that we all share equally. It crosses cultures, languages, and generations. It does not divide humanity — it connects us.
And yet even today, managing our time remains unnecessarily complicated, a model inherited from another era.
For more than four centuries, the Gregorian calendar has shaped the life of a large part of humanity. Adopted in 1582 to correct the drift of the Julian calendar, it gradually became the global standard for civil, scientific, and economic activities. Its remarkable astronomical accuracy largely explains its longevity and success. However, it is not without structural oddities and inconsistencies. Many of its features, inherited from superstitions and religious beliefs rather than logic, create practical difficulties and have long fueled proposals for reform.
The time has come to pay special attention to the oddities that our calendar still carries. Here are the main quirks that justify a serious and modern revision of the Gregorian calendar currently in use.
So why change our calendar ?
1. The Gregorian calendar, an unfinished reform :
Introduced about 440 years ago, the Gregorian calendar was a big step forward in organizing time. Yet, this reform didn’t go all the way: it kept several flaws inherited from the Julian and Roman calendars, which are more than two thousand years old.

2. The month of February, a strange month:
With its 28 days, February is a real oddity. This peculiarity goes back to the Roman calendar, which at the time had 355 days—four months of 31 days, seven of 29 days, and one month of 28 days. The Romans, being superstitious, believed that even numbers brought bad luck. So they favored months with an odd number of days. However, to reach a total of 355 days, there had to be a month of 28 days. February, associated with the dead and funeral rites, was chosen to carry this exception.
It must be said that this old superstition has left a curious mark on our current calendar.

3. Unequal length of months:
The Gregorian calendar has kept a very irregular distribution of days: one month of 28 or 29 days, four months of 30 days, and seven months of 31 days. Why are months different lengths? This irregularity forces us to constantly check the number of days in each month to plan our activities and deadlines.

4. Birthdays always on different days:
In the Gregorian calendar, a birthday changes the day of the week from one year to the next. A birthday that falls on a Monday this year might fall on a Wednesday the following year. This makes it tricky to keep track because annual events, meetings, and activities never fall on the same day of the week from one year to the next.

5. An uneven distribution of quarters:
The four quarters of the year don’t have the same number of days: the first has 90, the second 91, and the last two 92. This uneven distribution makes financial, economic, and statistical comparisons from one quarter to another tricky. Adjustments are often needed to account for the different number of days and get truly meaningful comparisons.

6. Complex Planning:
Every year, schools, businesses, and organizations have to readjust their calendars and schedules. The dates keep shifting from one day of the week to another, making it impossible to repeat the exact same annual schedule.
Why start over every year with something that could be permanent?

7. Weeks that span two months:
In the Gregorian calendar, the weeks at the beginning and end of a month usually span two months. This situation unnecessarily complicates the preparation of weekly and monthly reports, as well as tracking activities and results.
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8. A complicated perpetual calendar:
Every year requires a different setup of our calendar. You have to use one of the 14 possible calendar templates. This situation forces us to renew our calendar every year, whereas a true perpetual calendar could keep exactly the same structure from one year to the next.

9. Unnecessarily complicated administrative management:
Months of varying length make many repetitive tasks more difficult: preparing medications, renewing prescriptions, managing subscriptions, payroll, statistics, budgets, billing, etc. These activities constantly have to account for the different number of days in each month and in reference periods.

10. A somewhat irrational historical origin:
The Gregorian calendar inherited several features from the Roman and Julian calendars, whose origins go back over two thousand years. It is therefore the result of many historical adjustments rather than a design based on principles of simplicity, regularity, and logic.
The main flaw of the Gregorian calendar isn’t its astronomical accuracy, but its big lack of consistency. After more than four centuries, isn’t it time to design a calendar suited to the needs of our era?
That’s exactly why the Fixed Modern Calendar was created. A simpler, more logical calendar, better adapted to our requirements for effective time management.
Managing our time well becomes a priority today.
What's the solution?
The Modern Fixed Calendar is a simple and universal model for managing our time. A calendar free from the anomalies that unnecessarily complicate our current calendar. A logical update to the current Gregorian calendar.
In control of our time
The Modern Calendar, a clear and universal vision:
A year of thirteen months of twenty-eight days each. Identical months of four weeks each where every week starts on the same day. The years become predictable.
The last week of the year is eight days long. The last day of the year is called Ĝis, « Goodbye » in Esperanto. It’s a day of transition for everyone. In leap years, an extra day is also added in the middle of the year, in the last week of the seventh month. This day is called Ferio, « Holiday » in Esperanto. These days mark moments outside the usual rhythm, either to highlight the transition between years or the anomaly of a leap year.
The names of the months and days are in Esperanto, the language that promotes understanding between peoples. Because time belongs to all humanity, its organization can be simple, stable, and shared.
The Modern Calendar is an invitation to simplify our time management by harmonizing our years. Living time with clarity.
One world. One time. A simple and modern structure !
Total Predictability : The first day of the week is always a Monday (Lundo) and the last a Sunday (Dimanĉo). Birthdays always fall on the same day of the year.
- Economic Fairness :Each month has exactly the same number of working days. No more loss-making Februarys and overloaded Marches for businesses.
Unity Through Language : By using Esperanto (Lundo… Dimanĉo), the calendar becomes neutral and accessible to all, without favoring any specific culture.
Mathematical Simplicity: A year of 13 months of 28 days, plus one extra day at the end of the year, is simple and repetitive math. No more puzzle-solving calendars.
The oddities of the gregorian calendar
Unequal months
Even after several revisions, the calendar is still composed of unequal months, designed on the basis of superstition or religious beliefs:
– 7 months of 31 days
– 4 months of 30 days
– 1 month of 28 days (or 29 days)
A wide variety of anual calendars
There are fourteen different versions of the Gregorian calendar. The current design of the calendar means that consecutive years are all different and birthdays always fall on different days.
Why the Fixed Modern Calendar?
To meet the needs of today’s society, it is necessary to bring order to our calendar and offer a more structured option, free of ambiguities and accessible to all people.
It is to meet this need that the Modern Fixed Calendar was designed: a clean, uniform, and repetitive calendar. The names of the days and months are in Esperanto, a universal language accessible to all people.
The Modern Fixed Calendar, a calendar full of common sense

A secular calendar
A calendar devoid of any religious connotation and which can be adapted to all religions.

A rational timetable
A calendar designed in a logical and systematic way aimed at a uniform and predictable organization of time.

A festive calendar
A calendar offering a day off for all at the end of the year and in leap years.

A solar calendar
A solar calendar allowing an efficient management of activities related to the cycles of the seasons.

A convenient calendar
A calendar that effectively meets the planning and scheduling needs of our daily activities.

A user-friendly calendar
A simple and easy-to-use calendar allowing for an accommodating experience for its users.

A universal calendar
A modern calendar with month and day names in the universal language Esperanto, thus facilitating international exchanges.

A balanced schedule
A calendar that effectively harmonizes practical and cultural aspects, ensuring an equitable distribution of days and months while meeting the needs of our societies.
In conclusion
What if our time finally became simple ?
Today, our calendar is irregular, unpredictable, and unnecessarily complex. Months vary, dates shift, and planning becomes a challenge.
The Modern Fixed Calendar changes everything.
13 months of 28 days. 4 perfect weeks per month. Every date falls on the same weekday, every year. A clear, stable, and logical structure—ideal for work, education, and everyday life. The names of the days and months in Esperanto, a language accessible to all.
And to mark the passage of time, a unique day—Ĝis—concludes the year, outside the weekly cycle, as a universal moment of transition. So less confusion and more consistency.
With the Modern Fixed Calendar : Time finally mastered.
The Excel file of the Modern Fixed Calendar
The following link allows you to download the Modern Calendar as an Excel file. The document consists of three tabs:
- Modern Calendar Rules : Indicates the rules governing the Modern Calendar.
- Modern : Displays the Modern Calendar allowing you to choose the desired year and including a date conversion table between the Gregorian Calendar and the Modern calendar.
- Gregorian : Displays the Gregorian calendar allowing you to choose the desired year.