IST is 1 hour 30 minutes ahead of GST all year. So 12:00 PM GST = 1:30 PM IST.
GST to IST conversion table
| GST | IST |
|---|---|
| 12:00 AM | 1:30 AM |
| 1:00 AM | 2:30 AM |
| 2:00 AM | 3:30 AM |
| 3:00 AM | 4:30 AM |
| 4:00 AM | 5:30 AM |
| 5:00 AM | 6:30 AM |
| 6:00 AM | 7:30 AM |
| 7:00 AM | 8:30 AM |
| 8:00 AM | 9:30 AM |
| 9:00 AM | 10:30 AM |
| 10:00 AM | 11:30 AM |
| 11:00 AM | 12:30 PM |
| 12:00 PM | 1:30 PM |
| 1:00 PM | 2:30 PM |
| 2:00 PM | 3:30 PM |
| 3:00 PM | 4:30 PM |
| 4:00 PM | 5:30 PM |
| 5:00 PM | 6:30 PM |
| 6:00 PM | 7:30 PM |
| 7:00 PM | 8:30 PM |
| 8:00 PM | 9:30 PM |
| 9:00 PM | 10:30 PM |
| 10:00 PM | 11:30 PM |
| 11:00 PM | 12:30 AM +1 day |
GST and IST difference through 2027
The gap between the two zones on each date range, including daylight saving time changes:
| Dates | Gulf Standard Time | India Standard Time | Difference |
|---|---|---|---|
| Sep 30, 2026 – Dec 31, 2027 | GST (UTC+4) | IST (UTC+5:30) | IST 1 hour 30 minutes ahead |
Best time to meet or call
- Working hours (9 AM–5 PM) overlap from 9:00 AM–3:30 PM GST (10:30 AM–5:00 PM IST), about 6 hours 30 minutes.
About Gulf Standard Time (GST)
The UAE and Oman use GST (UTC+4) all year with no daylight saving time. It's used in Dubai, Abu Dhabi and Muscat.
About India Standard Time (IST)
India uses one time zone, IST (UTC+5:30), all year. India does not observe daylight saving time, so its difference from the US and UK changes when they change their clocks. It's used in all of India, including New Delhi, Mumbai, Bengaluru, Hyderabad, Chennai and Kolkata.
Frequently asked questions
What time is 12 PM GST in IST?
12:00 PM GST is 1:30 PM IST.
How many hours ahead or behind is IST from GST?
IST is 1 hour 30 minutes ahead of GST, all year.
Does GST change for daylight saving time?
No. The UAE and Oman use GST (UTC+4) all year with no daylight saving time.
Does IST change for daylight saving time?
No. India uses one time zone, IST (UTC+5:30), all year. India does not observe daylight saving time, so its difference from the US and UK changes when they change their clocks.
What is the best time for a call between GST and IST?
Right now, working hours overlap from 9:00 AM–3:30 PM GST (10:30 AM–5:00 PM IST), about 6 hours 30 minutes.
More time zone conversions
Sources
Reviewed by Gurmej Singh, Founder, Divy Digital Hub · Last reviewed: Wednesday, September 30, 2026. All calculations run in your browser. Editorial policy.