Hindu Fasts & Special Dates

The Hindu religious year is punctuated by vrats (fasting observances) and special dates tied to the movements of the Moon and Sun. Some fall on specific Tithis (lunar days), some on lunar phases (full moon, new moon), and some on the Sun's transit into a new zodiac sign. Nakshatrica computes all four major observance calendars — Ekadashi, Purnima, Amavasya, and Sankranti — for any year using the Swiss Ephemeris with the sidereal Lahiri Ayanamsha.

Ekadashi — the 11th Tithi

Ekadashi (Sanskrit: एकादशी, "eleventh") falls twice each lunar month — once in the waxing fortnight (Shukla Paksha) and once in the waning (Krishna Paksha) — giving 24 Ekadashis per year, occasionally 25 in adhika-mas (extra-month) years. It is the primary Vaishnava fasting day, dedicated to Lord Vishnu. Traditional observance includes complete fasting from grains, beans, and certain vegetables (called anna-tyaga), or partial phalahar (fruits and dairy). Each Ekadashi has a specific name — Kamada, Varuthini, Mohini, Nirjala, Yogini, Devshayani, Kamika, Ajā, Parivartini, Indira, Papankusha, Rama, Utpanna, Mokshada, Saphala, Putrada, Shattila, Jaya, Vijaya, Amalaki, Papmochani, Kamada, and others — with distinct scriptural stories from the Puranas.

Purnima — the full moon

Purnima (Sanskrit: पूर्णिमा, "full") marks the completion of the Shukla Paksha, when the Moon is diametrically opposite the Sun. There are 12 Purnimas per year (13 in adhika-mas years), each named after the Nakshatra it falls in or the lunar month. Major Purnimas include Guru Purnima (honoring spiritual teachers, in Ashadha), Sharad Purnima (autumn full moon, associated with Rasa Lila), Kartik Purnima (Dev Diwali), Buddha Purnima (Buddha's birth, Vaishakh), and Holi Purnima. Purnima is auspicious for Satyanarayan Puja and for beginning spiritual practices.

Amavasya — the new moon

Amavasya (Sanskrit: अमावास्या) is the new moon day — when the Moon is conjunct with the Sun and invisible from Earth. Traditionally observed as a day for honoring departed ancestors through Shraddha and Pitru Tarpan rituals. Significant Amavasyas include Mauni Amavasya (silence vow, Magha), Somvati Amavasya (when it falls on Monday), Kartik Amavasya (Diwali night), and Bhadrapada Amavasya (end of Pitru Paksha / Mahalaya). New moon nights are also considered powerful for tantric practices and Kali worship.

Sankranti — the Sun's zodiac transit

Sankranti (Sanskrit: संक्रान्ति, "transit") marks the Sun's entry into a new zodiac sign — a solar event rather than a lunar one. There are 12 Sankrantis per year, one for each sign, spaced roughly a month apart. Notable Sankrantis include Makar Sankranti (Sun enters Capricorn, marks Uttarayan — the northward journey, celebrated as Pongal in Tamil Nadu, Bihu in Assam, Lohri in Punjab), Mesh Sankranti (Sun enters Aries, marks the Vedic solar new year — Baisakhi in Punjab, Vishu in Kerala, Poila Boishakh in Bengal), and Karka Sankranti (Sun enters Cancer, marks Dakshinayan — the southward journey). Sankranti days are auspicious for charity (daan), ritual bathing, and worship of the Sun.

Why location and timing matter

Vrat dates are anchored to the Tithi at sunrise — which depends on your local sunrise time and therefore your location. A Purnima Tithi may end at 4:15 AM in Delhi but at 5:03 AM in Chennai; the observance day differs. Nakshatrica auto-detects your location and computes the ruling Tithi for local sunrise, so the calendar you see is accurate for where you are. Some traditions also differ between Purnimanta (month ends at Purnima, used in North India) and Amanta (month ends at Amavasya, used in South India) — our Ekadashi calendar uses the standardized Purnimanta system so names align across regions.

Explore the rest of Nakshatrica

Vrat observance is one dimension of Hindu religious life. Nakshatrica offers a full suite of Vedic astrology tools to complement your practice — all free and precise.