एकादशी
Ekadashi — The Eleventh Tithi
एक (eka, "one") + दश (daśa, "ten") — the eleventh Tithi of each Paksha, observed twice a month with a Vishnu fast by many Hindus, especially Vaishnavas. See our full Ekadashi guide for fasting practice and significance.
Krishna Paksha Ekadashi falls in the waning fortnight (before Amavasya); Shukla Paksha falls in the waxing fortnight (before Purnima). Approximate — confirm with a local Panchang before fasting.
See our Tithi-level explanation of Ekadashi, or the anchor dates it's derived from: Amavasya and Purnima. See also Purnima vs Ekadashi: What's Actually Different?