BhaktiVedCalendar sources and calculation method
Place, time and tradition
Daily tithi and nakshatra are calculated at local sunrise using the selected city’s date and IANA timezone, including daylight-saving changes. The implementation uses amanta months, PyEphem positions and an approximate Lahiri ayanamsa.
Two different date sources
Annual festival dates come from a fixed Andhra / Telangana reference table; changing the city does not recalculate those dates. Monthly tithi observances are calculated for the selected city.
Fasting traditions can apply additional observance rules. The simplified calculation does not implement every Smartha, Vaishnava or regional rule, and should not be treated as a complete fasting calendar. Confirm with your family or tradition’s panchang.
Validation coverage
A Hyderabad reference check on 2026-10-27 found matching sample dates but also Ekadashi differences around 2026-05-26/27 and 2026-11-20/21. These remain under editorial review. Other years, cities and traditions have not been comprehensively validated.