Ekādaśī · the eleventh lunar day
Ekādaśī
Ekādaśī is a vrata especially important in Vaiṣṇava traditions. It occurs in both the bright and dark lunar fortnights, so it normally returns twice during a lunar month. Devotional practice varies and may include fasting, prayer, recitation, worship, or other disciplines appropriate to a person's tradition and circumstances.
What is visible in the calculation?
Ekādaśī is a tithi defined by the Moon–Sun angle.
A tithi is each 12-degree increase in Moon–Sun elongation. Ekādaśī is the eleventh tithi of either pakṣa: Śukla Ekādaśī in the bright, waxing fortnight or Kṛṣṇa Ekādaśī in the dark, waning fortnight. The astronomical interval is objective, but a calendar still needs a convention for connecting that moving interval with a local date.
What Open Pañcāṅga checks
This guide checks the tithi at local sunrise.
Open Pañcāṅga currently identifies Ekādaśī vrata when Ekādaśī prevails at sūryodaya, the local sunrise. The result states the sunrise time, whether the tithi is Śukla or Kṛṣṇa Ekādaśī, and the calculated Moon–Sun elongation. These are the rules used here. Some traditions use additional checks and may assign the fasting date differently.
Why another pañcāṅga may show a different date
Some Vaiṣṇava calendars also examine the time before sunrise.
A pre-sunrise period used by some Vaiṣṇava Ekādaśī rules. These rules examine whether the preceding Daśamī tithi continues into this period.
A group of exceptional cases in which the fast may be assigned to Dvādaśī rather than the date selected by a simple sunrise test.
The prescribed period for completing or breaking the vrata, normally calculated separately on the following day.
A complete sampradāya calendar may therefore need more than the tithi at sunrise. Aruṇodaya purity, Mahādvādaśī exceptions, and pāraṇa windows remain future capabilities; their eventual methods and sources will be named so users can see why dates may differ.
A named annual specialization
Devaśayanī Ekādaśī adds the regular amānta Āṣāḍha condition.
When Śukla Ekādaśī is present at sunrise during the regular month Āṣāḍha in the amānta calendar used here, Open Pañcāṅga shows Devaśayanī Ekādaśī, also called Āṣāḍhī Ekādaśī, instead of repeating the general Ekādaśī observance.