On 1st September 1947 the Indian Standard Time (IST) was introduced as the official time for the whole country.
The Indian Standard Time is observed throughout India, with a time offset of UTC+5:30. This means that India is five and a half hours ahead of Greenwich Mean Time.
Indian Standard time (IST) is the time zone observed throughout India, with a time offset of UTC+05:30. India does not observe daylight saving time or other seasonal adjustments. In military and aviation time IST is designated E* ("Echo-Star").
Indian Standard Time is calculated on the basis of 82.5°E longitude in the city of Mirzapur, Uttar Pradesh, which is situated approximately on the corresponding longitude reference line.
