The Calendar of Ancient Egypt
The Egyptian year was divided into 12 months of 30 days; at the end of the year 5 additional days (the "epagomenal days") were added so one year had 365 days.
The year was further divided into three seasons:
- Achet "inundation (of the Nile)"
- Peret "winter"
- Shemu "summer"
Each season consisted of four months that were numbered from one to four. These 12 months later received names derived from certain religious feasts:
The ancient Egyptians dated their documents by the years of the king's reigns and not by a continous era like nowadays Gregorian calendar, for example:
"Year 12 of Pharaoh Psametik, 3rd month of Peret, day 23"
To convert those dates into the Julian calendar you can use this date converter; choose a period (Late Period, Ptolemaic Kings, Macedonian Calendar or Roman Emperors), specify the reign, year, month and day (optionally) and click on "convert date".
All calculations are based on the tables in Skeat, Reigns of the Ptolemies (1969), Pestman, Chronologie égyptienne d'après les textes démotiques (1967) and Pestman, Les papyrus démotiques de Tsenhor (1994).
The system expects that the user knows what (s)he's doing; ahistoric entries will result in mathematically correct but otherwise rather useless dates.
Not specifying a day will result in calculation of both the first and last day of the given month.