How do I find out when my childs bar/bas mitzvah date will be?
Enter your child’s common date of birth. The Jewish date of birth will instantaneously appear. Modify the Jewish year to be 13 higher. Then look again at the common date for your answer. Of course you’ll probably want to use the Saturday that immediately follows that date. And if your child was born after sundown, then you’ll have to add one day to the Jewish date. See question 106 for a discussion on this.