The Coptic Calendar
Orthodox Copts worldwide rely on the Coptic calendar to determine the dates of religious holidays and rituals. Derived from the ancient Egyptian calendar, it is still officially used in modern-day Egypt.
Orthodox Coptic church service.
©iStockphoto.com/DZarzycka
The Coptic calendar, also called the Alexandrian calendar, is neither to be confused with the ancient Egyptian calendar, from which it derives, nor with the Ethiopian calendar, which is closely related but uses different year numbers.
Tied to the Julian Calendar
Sharing the same rules to determine when a leap day is added, the Coptic calendar has been synchronized with the Julian calendar since 25 BCE.
The year starts on the Feast of Neyrouz on the first day of Tout, the first month. This falls on August 29 in the Julian calendar if the following year is a common year and August 30 if it is a leap year. Until the end of the current century, this corresponds to September 11 and September 12 in the western Gregorian calendar.
Although its name sounds very similar to that of the Persian spring festival, Nowruz, the Feast of Neyrouz is otherwise unrelated.
Calendar Structure
Months in the Coptic Calendar
| Months (Coptic / Arabic) | Number of Days |
|---|---|
| Tout / Tūt | 30 |
| Paopi / Bābah | 30 |
| Hathor / Hātūr | 30 |
| Koiak / Kiyahk | 30 |
| Tobi / Ṭūbah | 30 |
| Meshir / Amshīr | 30 |
| Paremhat / Baramhāt | 30 |
| Parmouti / Baramūdah | 30 |
| Pashons / Bashans | 30 |
| Paoni / Ba’ūnah | 30 |
| Epip / Abīb | 30 |
| Mesori / Masrá | 30 |
| Pi Kogi Enavot / Nasī’ | 5 or 6 |
The Coptic calendar year is divided into 13 months. The first 12 months have 30 days. The last month, called Pi Kogi Enavot or Nasie and referred to as an epagomenal month, has 5 days in a common year and 6 days in a leap year.
Months in the Gregorian calendar
When Was Year 1?
Year 1 in the Coptic calendar started on August 29, 284 in the Julian calendar. It was the year that Diocletian became Roman Emperor. In commemoration of the widespread prosecution of Christians during that era, years in the Coptic calendar are designated A.M., which is short for Anno Martyrum, Year of the Martyrs.
Leap Year Rules
Mirroring the leap year rules of the Julian calendar, a leap day is added every four years without exception. However, the extra day is always added at the end of the year preceding the Julian leap year. In practice, a sixth day is added to the last month of the year, Pi Kogi Enavot.
This means that the Coptic leap day is always 171 days before the Julian leap day. In that period of time, the months in the Coptic calendar, therefore, begin one day later than in the Julian calendar.
Leap years in the Gregorian calendar
History and Background
The Coptic calendar is arguably the oldest calendar system that is still in widespread use. It has its roots in the ancient Egyptian calendar, whose earliest documented implementations date back to the 5th millennium BCE. However, it has undergone a number of reforms through the centuries, attaining its current form in 25 BCE.
The ancient Egyptian calendar did not feature any mechanisms to keep it in sync with the tropical year, so each calendar year had 365 days. Since an average tropical year lasts for approximately 365.24219 days, the calendar system failed to correctly reflect the astronomical seasons in the long-run.
In an attempt to fix this problem, a leap day mechanism was formally introduced in 25 BCE. A Roman province at the time, Egypt's calendar was reformed to mirror the Julian calendar, which had been introduced in the Roman Empire only a few years prior. Since then, the Coptic calendar has been synchronized with the Julian calendar.