The fast for Ekadashi is related to the three-day routine. Thus, there can be at least 24 Ekadashi in a year, but in the case of Adhik Mas (extra months), this number can also be 26. There are two Ekadashi due to having two paksha's in a month, one on the Shukla Paksha and the other on the Krishna Paksha. Ekadashi is considered a day dedicated to Bhagwan Vishnu.
As per the Hindu calendar, each month’s 11th tithi is called Ekadashi.
