Calendars of Faerûn

The Calendar of Harptos: There are 365 days in the year, split up into twelve months of thirty days each with five holidays that fall between some months. The names of the months are given in both the formal names and the common ones. The seasons run like they do for the northern hemisphere; Hammer is like January and Flamerule is like July. Each week consists of ten days, called a tenday.

The holidays are Midwinter, Greengrass, Midsummer, Highharvestide and The Feast of the Moon. Midwinter falls between Hammer and Alturiak, Greengrass between Tarsakh and Mirtul, Midsummer is between Flamerule and Eleasis, Highharvestide is between Eleint and Marpenoth, and The Feast of the Moon is between Uktar and Nightal.

Dalereckoning (DR): Dalereckoning is taken from the Year of Sunrise, when the Standing Stone was raised by the elves of Cormanthor and the human Dalesfolk. Since this time, humans were permitted by the Elven Court to settle in the more open regions of the forests. In some texts, primarily those which do not have direct ties to Dales history, Dalereckoning is called Freeman's Reckoning (FR). The calendar is widely used in Faerûn but has not spread beyond its shores. Dalereckoning is the most common year measurement.