Multiple choice Indian Standard Time is ………… hours ahead of GMT/UTC: 5.5 hours 5.00 hours 5.7 hours 5.01 hours Reveal answer Fill a bubble to check yourself A Correct answer Explanation Indian Standard Time (IST) is calculated based on the 82.5 degrees East longitude. It is exactly 5 hours and 30 minutes (5.5 hours) ahead of Greenwich Mean Time (GMT) or Coordinated Universal Time (UTC).