Rosh Chodesh


Why does Rosh Chodesh (new moon) occur a day or two after the new moon in the secular calendar?


thank you



  1. There is no necessary correlation between the secular months and Rosh Chodesh.

    Each month in the Jewish calendar lasts either twenty-nine days or thirty days. For example, this coming month of Tishrei begins on the 26th of September. The first day of the following month of Cheshvan is also on the 26th of the month (October). However, due to the fact that almost every Jewish month is only twenty-nine days long every two months, Rosh Chodesh and the secular date tend to be a day earlier than it was the previous month.

    Best wishes from the Team