GMTtoISTGreenwich Mean Time to India Standard Time
GMT
Greenwich Mean Time (GMT)IST
India Standard Time (GMT+5:30)Mutual Working Window: 3 Overlapping Hours
Recommended calling window between GMT and IST
Both locations share 3 overlapping standard business hours (9:00 AM – 5:00 PM). This is the premier window for real-time video conferences, corporate calls, and instant collaboration without outside-hours disruption.
24-Hour Schedule Conversion Matrix
Compare every hour of the day between GMT and IST.
| GMT Time (Greenwich Mean Time) | IST Time (India Standard Time) | Status & Recommendation |
|---|---|---|
| 00:00AM | 05:00AM | ⚪ Outside Work Hours |
| 01:00AM | 06:00AM | ⚪ Outside Work Hours |
| 02:00AM | 07:00AM | ⚪ Outside Work Hours |
| 03:00AM | 08:00AM | ⚪ Outside Work Hours |
| 04:00AM | 09:00AM | ⚪ Outside Work Hours |
| 05:00AM | 10:00AM | ⚪ Outside Work Hours |
| 06:00AM | 11:00AM | ⚪ Outside Work Hours |
| 07:00AM | 12:00PM | ⚪ Outside Work Hours |
| 08:00AM | 13:00PM | ⚪ Outside Work Hours |
| 09:00AM | 14:00PM | 🟢 Ideal Meeting Window |
| 10:00AM | 15:00PM | 🟢 Ideal Meeting Window |
| 11:00AM | 16:00PM | 🟢 Ideal Meeting Window |
| 12:00PM | 17:00PM | 🟡 Feasible (Shoulder Hour) |
| 13:00PM | 18:00PM | 🟡 Feasible (Shoulder Hour) |
| 14:00PM | 19:00PM | 🟡 Feasible (Shoulder Hour) |
| 15:00PM | 20:00PM | 🟡 Feasible (Shoulder Hour) |
| 16:00PM | 21:00PM | ⚪ Outside Work Hours |
| 17:00PM | 22:00PM | ⚪ Outside Work Hours |
| 18:00PM | 23:00PM | ⚪ Outside Work Hours |
| 19:00PM | 00:00AM | ⚪ Outside Work Hours |
| 20:00PM | 01:00AM | ⚪ Outside Work Hours |
| 21:00PM | 02:00AM | ⚪ Outside Work Hours |
| 22:00PM | 03:00AM | ⚪ Outside Work Hours |
| 23:00PM | 04:00AM | ⚪ Outside Work Hours |
Frequently Asked Questions
What is the time difference between GMT and IST?
IST is 5 hours 30 minutes ahead of GMT. When it is 12:00 PM (noon) in GMT, the current synchronized time in IST is 5:30 PM.
What are the overlapping working hours between GMT and IST?
There are 3 overlapping standard business hours (9:00 AM – 5:00 PM) between GMT and IST. The optimal scheduling window is 9:00 AM – 12:00 PM in GMT (2:00 PM – 5:00 PM in IST).
Does daylight saving time affect the conversion between GMT and IST?
Yes. GMT observes daylight saving shifts, moving the offset by 1 hour on scheduled transition dates.
What regions and major cities observe GMT and IST?
GMT (Greenwich Mean Time) is primarily observed across Western Europe & West Africa (United Kingdom, Ireland, Portugal, Ghana) (key hubs include London, Dublin, Lisbon, Accra). IST (India Standard Time) is observed across South Asia (Republic of India & Sri Lanka) (key hubs include New Delhi, Mumbai, Bengaluru, Hyderabad).
What is 9:00 AM GMT in IST?
9:00 AM in GMT corresponds to 2:30 PM in IST. You can cross-reference every hour of the day in the 24-hour visual schedule table above.
Which time zone is ahead, GMT or IST?
IST is ahead by 5 hours and 30 minutes.