Chaudas falls on the Krishna Paksha Chaturdashi of each traditional Hindu lunar month. Below are the monthly Chaudas fasting dates in 2023. ‘Krishna Paksha’ is the dark fortnight of a lunar month. It is the 14th day after full moon (Purnima) or more easy calculation one or one day before Amavasya. Shiva devotees observe the day with vrat, special prayers and pujas. Some devotees also keep vigil all night as in Mahashivratri . Chaudas Dates in 2023 (Indian Standard Time) January 20 February 18 – Annual Mahashivratri March 20 April 18 May 17 June 16 July 15, 2023 – August 14 September 13 October 12 November 11 December 11