The year is divided in 12 months: Mar, Lesthis, Gheyrich, Byr, Quiyene, Sielle, Dur, Shandine, Verdine, Dachten, Porelle, and Nevelle. Each month is further divided in two Quiyana of fifteen days. The first Quiyana, Ar, is composed of the weeks Wer and Ar. The second Quiyana, Ba'Ar, holds the weeks Myr and Ba'Ar. Each week has seven days: Merrihynday, Tyrday, Faelday, Midnday, Beynday, Corrilday and Perrynday. The day of rest, Gonwynday falls before Merrihynday in the weeks of Ar and Ba'Ar. The six feast days lie outside months and weeks. In addition to Algonday (the last day of the year), the four primary feast days track the seasons. Maidenday (the first day of the year) is the Spring Equinox. Welanday falls on the Summer Solstice, Arday on the Autumnal Equinox and Norday on the Winter Solstice. Primaday is celebrated once every four years following Algonday and marks the end of each Primature.
Standard notation for recording dates in the Aen Calendar consists of writing the name of the month, followed by the week, the day and the year since the construction of Temple Aen and occassionally, the name of the age. Short notation is to write the year and the day of the year separated by a dot.