While the five-day festivities of Diwali 2023 will be marked from November 10 (Dhanteras 2023) and go on till November 15, there are various questions on when is Bhai Dooj. Also known as Bhau Beej and Yama Dwitiya, Bhai Dooj is celebrated on the Shukla Paksha Dwitiya tithi in the Hindi month of Karthik.