The Bangla Calendar (Bengali: বঙ্গাব্দ Bônggabdo or বাংলা সন Bangla Shôn) or Bangla calendar may refer to the sidereal solar used by the Bangla people in their calendar officially used in Bangladesh. The year begins on Pohela Boishakh, which falls on 14 April according to the tropical calendar in Bangladesh.
The current Bangla year is Template:BANGLAYEAR. The Bangla year is 594 less than the AD or CE year in the Gregorian year if it is before Pôhela Boishakh, or 593 less after Pôhela Boishakh.
Bangabda Bangla calendar, also known as 'Bangla Sal', was promulgated by the Mughal emperor Akbar in 1584 AD. The new calendar was initially known as Tarikh-e-Elahi and was introduced on 10 or 11 March 1584. Though the new calendar was promulgated in the twenty-ninth year of Akbar's reign, it dates from his ascension to the throne on 5 November 1556.
The purpose of Tarikh-e-Elahi was to glorify Akbar's ascent to the throne as well as to facilitate the collection of revenue. The Mughal emperors had been using the Hijri calendar for the purposes of collecting revenue. However, as Abul Fazl explains in Akbar Namah, the use of the Hijri calendar was irksome to the peasantry because there was a difference of 11 or 12 days between the lunar and the solar years, with 31 lunar years being equal to 30 solar years. Revenue was collected according to the lunar year, whereas the harvest was dependent on the solar one. From the beginning of his reign, Akbar had felt the need of introducing a uniform, scientific, and workable system of calculating days and months through a reformed calendar. With this end in view, he commissioned Amir Fathullah Shirazi, a distinguished scientist and astronomer, to make the changes.