Indian calendars are timekeeping instruments that reflect various cultural influences over time, reflecting the country´s multicultural history. Thus, there are four main Indian calendars used for different purposes: Vikram Samvat, Saka Samvat, the Hijri or Muslim calendar and the Gregorian calendar. The Vikram Samvat is a lunar calendar, with year zero beginning in 57 B.C., highlighting the deep cultural roots of the Indian people. The Saka Samvat calendar is a solar calendar, similar to the Gregorian calendar, and is used for both civil and religious purposes, with year zero beginning in 78 A.D. (Saka Era). In this regard, it is important to refer the contributions of ancient texts, such as the Vedanga Jyotisha and the Surya Siddhanta. In addition to the main calendars, other Indian calendars are also used by Indian people, such as, the Hijri or Muslim calendar, which is a lunar calendar consisting of 12 lunar months in a year of 354 days. The Gregorian calendar, on the other hand, is a solar calendar consisting of 12 months in a year of 365 days, and is primarily used for administrative purposes. In 1957, after India´s independence, the Calendar Reform Commission established a standard calendar for all states of India, and adopted the Saka Samvat as the Indian national calendar.
Paulo Nuno Martins (Thu,) studied this question.