Notes: All timings are represented in 12-hour notation in local time of Ashburn, United States with DST adjustment (if applicable).
Hours which are past midnight are suffixed with next day date. In Panchang day starts and ends with sunrise.
Kali Chaudas is also known as Bhut Chaturdashi. Kali Chaudas is mainly observed in Western states especially in Gujarat.
Kali Chaudas is observed during Chaturdashi Tithi during Diwali festivity. However Kali Chaudas day should not be mixed with Roop Chaudas and Narak Chaturdashi as it might fall one day before of Narak Chaturdashi. The day of Kali Chaudas is decided when Chaturdashi prevails during midnight which as per Panchang is known as Maha Nishita time.
As rituals of Kali Chaudas involve visiting crematorium during midnight for offering Puja to the Goddess of darkness and to Veer Vetal, the day of Kali Chaudas is decided when Chaturdashi prevails during midnight.
It seems that most Panchang do not make such distinction and list Kali Chaudas with Roop Chaudas and Narak Chaturdashi. Hence one has to be cautious while looking for Kali Chaudas date.
Further Kali Chaudas should not be confused with Bengal Kali Puja which is observed one day after Kali Chaudas when Amavasya Tithi prevails during midnight.