open-source tamil calendar calculation engine using precise solar transit astronomy, lahiri ayanamsa, and the traditional 13-ghatika rule. சூரிய பெயர்ச்சி, லஹிரி அயனாம்சம் மற்றும் பாரம்பரிய 13 கடிகை விதியை அடிப்படையாகக் கொண்டு தமிழ் காலண்டர் தேதிகளை கணக்கிடும் திறந்த மூல நிரல்.

A Bikram Samvat Calendar for Android.

Indian calendar that covers expected festivals, government holidays and good to know days as json.

A simple utility to show the details of the day per Tamil calendar

Bharatiya calendar infrastructure — Panchang, festivals, muhurat, regional calendars

Free, open-source Telugu Panchangam — any city, any date. The sky has no expiry date.

Ekadashi API & Web Calendar 🕉️. An astronomical calculator for accurate Ekadashi fasting dates using Sun-Moon longitude and the Arunodaya rule. Includes Telegram bot and REST API

Sankashti Chaturthi & Purnima API 🌙. Accurate Hindu lunar calendar calculator using Sun-Moon angular mathematics. Public REST API with Purnima and Sankashti dates.

Daily Hindu calendar with tithi, nakshatra, sunrise timings, and festival context.

Amavasya & New Moon REST API 🌑. High-accuracy Hindu Panchang calculator using astronomical math. Includes monthly spiritual significance and full year lunar calendar

Sankashti Chaturthi Moonrise PWA — tiny installable app for tithi-based moonrise tracking

Open Source Amavasya & New Moon API. Accurate Hindu Lunar Calendar calculator using astronomical moon-sun positions. Free REST API for developers.

Vedic Astronomical Audit tool.

Panchang API. Tithi, nakshatra, yoga, karana plus 15 muhurtas including rahu kaal, abhijit, brahma, varjyam, chandrabalam, tarabalam.

High-precision Vedic Panchang engine for PHP/Laravel with Swiss Ephemeris, festivals, muhurta, eclipses, and raw JSON export.

A lightweight, free JSON API providing accurate Sankashti Chaturthi dates, moonrise timings, and fasting schedules for developers.

Subscription-first Hindu panchang and alarm app for Android. Swiss Ephemeris sub-milliarcsecond precision, Dashami-Viddha / Adhik Maas / Kshaya correctness. AGPL v3.