Portal:India/SC Summary/SA Indian Standard Time

Indian Standard Time (IST) is the time observed throughout India, with a time offset of UTC+5:30. India does not observe daylight saving time (DST) or other seasonal adjustments, although DST was used briefly during the Sino–Indian War of 1962, and the Indo–Pakistani Wars of 1965 and 1971. In certain time-zone maps, IST is designated as E*.

Indian Standard Time is calculated on the basis of 82.5 °E longitude which just west of the town of Mirzapur, near Allahabad in the state of Uttar Pradesh. The latitude difference between Mirzapur and the Royal Observatory, Greenwich in the UK translates to an exact time difference of 5 hours and 30 minutes. Local time is calculated from a clock tower at the Allahabad Observatory (25.15°N, 82.5°W) though the official time servers are located in New Delhi. (more...)