Passover lasts for either seven or eight days, depending on the tradition and location:

• In Israel, Passover is observed for seven days, as prescribed in the Torah, with the first and last days being full holidays (yom tov)

• Outside of Israel, particularly in the Diaspora, Passover is celebrated for eight days. This includes an additional day at the beginning and end of the holiday, following rabbinic tradition to extend the observance

• Reform and Reconstructionist Jewish communities often observe Passover for seven days regardless of location

The holiday begins on the 15th day of the Hebrew month of Nisan, which typically falls in March or April, and commemorates the Exodus of the Israelites from Egypt

. In summary:

• Seven days : Observed in Israel and by some Jewish groups (Reform, Reconstructionist).
• Eight days : Observed by most Jews in the Diaspora (outside Israel), including Orthodox communities.

This explains why Passover duration can be either seven or eight days depending on Jewish customs and geography