How Many Days Were in a Week in Ancient Greece?

In Ancient Greece, the concept of timekeeping was quite different from what we are familiar with today. While we now have a standard week consisting of seven days, the ancient Greeks had a rather unique system when it came to counting days.

Ancient Greek Calendar

The ancient Greek calendar, known as the Attic calendar, was primarily lunar-based. It followed the phases of the moon to determine the passing of time. However, instead of dividing the month into weeks like we do today, they used a system based on three distinct periods: Noumenia, Mên, and Synodion.


Noumenia marked the beginning of each month in the ancient Greek calendar. On this day, people would gather to celebrate and honor various gods and goddesses associated with that particular month. The Noumenia took place during the first sighting of the new moon.


Following Noumenia was Mên, which represented roughly 14-15 days in length. This period began after the first crescent moon became visible in the night sky. During Mên, people would engage in various activities such as farming or trading.


Lastly, Synodion marked the end of each month in the ancient Greek calendar. It occurred when two celestial events coincided: a conjunction between Mercury and Jupiter and a lunar eclipse. Synodion lasted for about 10-11 days.

No Weekdays

Unlike our modern concept of weekdays, there were no specific names for individual days within each period in Ancient Greece. Instead, they were commonly referred to by their numerical order within each period.

For example:

  • The first day of Noumenia was simply called “Day 1. “
  • The second day of Mên was referred to as “Day 2.

  • The seventh day of Synodion was known as “Day 7. “

This lack of named weekdays is one of the major differences between the ancient Greek calendar and our current calendar system.


In conclusion, the ancient Greeks did not have a fixed number of days in a week as we do today. Instead, they followed a lunar-based calendar system divided into three distinct periods: Noumenia, Mên, and Synodion.

Each period had its own unique characteristics and marked the passage of time in different ways. While there were no specific weekdays with individual names, days were denoted by their numerical order within each period. This unique approach to timekeeping offers us a fascinating glimpse into the ancient Greek civilization and their understanding of time.