: By entering the original date and time of a person's passing, the tool identifies the specific tithi and calculates which day it falls on in the current year.
A small but growing community on GitHub and Hindu dharma forums is working on open-source annual Tithi calculators with portable builds. Examples include Panchanga-Portable and JyotishTools . The advantage of open source is transparency: users can inspect the exact formula for sunrise, Tithi duration, and sandhi (junction) periods. annual tithi calculator portable