Kalki Dwadashi Vrata is dedicated to the Kalki Avatar of Lord Vishnu. In 2012, the date of Kalki Dwadashi Vrata is September 26. It is observed on the 12th day of the waxing phase of moon in Bhadrapad month. The importance of Kalki Dwadasi Vrat is mentioned in the Varaha Purana and is observed by staunch Vishnu devotees.
The fasting of Kalki Dwadashi begins on the previous day which is the Parivartini Ekadasi day. The fast is broken on the morning of the Dwadasi day. An idol of Lord Kalki is made using clay or turmeric and is placed on top of a pot filled with water. This idol is worshipped on the day. The idol is donated to a learned Sanyasi or immersed in water on the next day, the trayodashi day.