What is Naraka Chaturdashi?
Naraka Chaturdashi is the oil-bath morning in the five-day Diwali season. In North India it is often called Choti Diwali. In parts of South India the morning bath marks Tamil Deepavali. The day recalls Krishna defeating Narakasura, and households take an early bath with oil, wear clean clothes, and light lamps.
How the date is chosen
The rule used on Inner Light is that Krishna Chaturdashi must be present in the pre-sunrise abhyang snan window, from moonrise to sunrise. When Chaturdashi covers that window on the same civil morning as Amavasya evening (Lakshmi Puja), both observances share that date. Some regions also keep Kali Chaudas rites on nearby nights; this page keeps one consistent abhyang rule for every city.
Local sunrise and the civil date for your city are on this page.
How it is observed
Abhyang snan. Take an oil bath in the abhyang window before sunrise while Chaturdashi still holds.
Lamps and sweets. Light a few lamps, share sweets, and prepare the house for the main Diwali evening when it falls the same day or the next.
Regional names. Roop Chaudas, Choti Diwali, and Tamil Deepavali morning all point to this Chaturdashi bath tradition.