According to Jewish tradition, giving charity is a significant component of observing a fast day, a practice known as "Igra D'Tanisa"-understood as the spiritual reward of fasting expressed through charitable giving.
The established custom involves donating an amount equivalent to the value of meals that would have been consumed during the fast, multiplied by the number of household members.
The Adopt A Family Fund has been identified as a suggested recipient for such donations, directing support to needy families within the Chabad community in Israel.