The national calendar based on the Saka Era with Chaitra as its first month and a normal year of 365 days was adopted from 22 March 1957 along with the Gregorian calendar for the following official purposes: (i) Gazette of India, (ii) news broadcast by All India Radio, (iii) calendars issued by the Government of India and (iv) Government communications addressed to the members of the public.

s Dates of the national calendar have a permanent correspondence with dates of the Gregorian calendar : 1 Chaitra falling on 22 March normally and on 21 March in leap year.