How we calculate

Trust is the product. This page exists so that any date on this site can be traced to a stated rule, and so that you can tell whether a disagreement with another calendar is a bug or a difference of tradition. Those are not the same thing and we try never to blur them.

The engine

• Engine — DailyWorks drik-siddhanta panchanga engine
• Method — drik (observational/computed), not vakya
• Ayanamsa — Lahiri (Chitrapaksha)
• Version — 2026.08.1
• Festival dataset published through — 2030

Sunrise, sunset, moonrise and moonset are computed for the latitude, longitude and timezone you have set, with the standard refraction and disc-centre conventions. Everything downstream — Rahu Kalam, the muhurtas, the pradosha and nishita windows — is derived from those, which is why setting your location changes almost every time on the site.

Which period governs which festival

This is the single most useful thing to understand about Hindu dates, and the thing most calendars leave implicit. A festival does not simply fall on "the day of its tithi". Each has a governing period, and the day chosen is the one on which the tithi covers that period.

• Nishita — Maha Shivaratri, Krishna Janmashtami, Masik Shivaratri
• Madhyahna — Rama Navami, Ganesh Chaturthi
• Pradosha — Pradosh vrat, Diwali Lakshmi Puja, Holika Dahan
• Aparahna — shraddha and tarpana, Raksha Bandhan, Vijayadashami
• Arunodaya — Ekadashi
• Moonrise — Karwa Chauth, Sankashti Chaturthi
• Sankranti instant — Makar Sankranti and the other solar entries

A calendar that applies the sunrise tithi to all of these will get several of them wrong in most years. When you see a date on this site, the festival's own page states the rule it used under Why this date?.

When traditions disagree

They often do, and the disagreement is usually legitimate. Smarta and Vaishnava practice differ on a viddha Ekadashi. Amanta and purnimanta regions name the same fortnight after different months. Southern Deepavali and northern Diwali are different observances that share a name. We show the difference and name the rule rather than picking one silently — and where we have made an explicit editorial choice, such as following the ISKCON reckoning for Janmashtami, we say so on the page.

What we will not do is manufacture a date to avoid an empty space. If our dataset has no validated row for an observance in a given year, the page says so. A visibly missing festival is better than a plausible date nobody checked.

Known limits, stated plainly

• Sampradaya is advisory today. Setting Vaishnava or Smarta changes how observances are grouped and labelled; it does not yet change a computed date. The reckoning differences are real and we would rather not implement them approximately.
• The festival dataset runs to 2030. Later years are not empty because nothing happens — they are not published yet.
• Regional coverage is uneven. The dataset is strongest for the pan-Indian festivals and the major regional ones. Local temple utsavams and family traditions are largely absent.
• Most guides are unreviewed. Every guide page states its review status. Editorial text that has not been checked by a named scholar or practising priest says so on its face.
• Hindu observances only. Christian and Islamic festivals are not listed. If a date you expect is missing for that reason, that is the reason — see what this calendar covers.
• Government holiday lists are not an observance source here. We publish five national civic days and take nothing else from them. State holidays — including the many our upstream dataset labels pan-India but which are one state's — are not shown. If you need a public-holiday list, this is not the right page for it.
• Muhurta beyond the daily windows is not published here yet. Wedding, griha pravesh and vehicle-purchase muhurtas involve rules this site has not yet published, and an approximate muhurta is worse than none.

Corrections

If a date here is wrong for your tradition, we want to know which tradition and why — that is more useful than "this is wrong". The corrections log records what we have changed and when.