List of observances set by the Hebrew calendar

All observances begin at sunset the day prior to the Gregorian date listed unless otherwise noted, and end on nightfall of the date in question, which is defined as the appearance of three stars in the sky. On leap years (which occur every 2–3 years) an extra month, Adar II, is added and certain holidays move accordingly, and it is mentioned in the notes section. All fasts other than Yom Kippur and Tisha b'Av begin at dawn of the day listed.
Holidays for the Jewish calendar year of 5781 (2020–2021).
Yom tov for the Three Pilgrimage Festivals (Pesach, Shavuot, and Sukkot) is observed for 1 day in Israel and in Reform and most Reconstructionist communities around the world, and is observed for 2 days in Orthodox and most Conservative communities outside Israel, because of "yom tov sheni shel galuyot". In the table, these are referred to as 1-day and 2-day communities.