IST to GST Time Converter

When it is 9:00 AM IST, it is 7.5:00 AM GST. Gulf Standard Time (GST, UTC+4) is 1.5 hours behind India Standard Time (IST, UTC+5:30). Your working-hours overlap window is 10.5:00 AM–5:00 PM IST (9:00 AM–3.5:00 PM GST).

IST to GST Conversion Table

Major Cities Using IST and GST

India Standard Time (IST): Mumbai, Delhi, Bangalore, Chennai, Kolkata, Colombo.

Gulf Standard Time (GST): Dubai, Abu Dhabi, Muscat.

How many hours between IST and GST?

IST is UTC+5:30 and GST is UTC+4, a difference of 1.5 hours. GST is behind IST. This difference can shift by an hour in either direction during Daylight Saving Time transitions — if one zone observes DST and the other doesn't, the offset narrows or widens for part of the year.

Business Hours Overlap: IST ↔ GST

Assuming a 9:00 AM – 5:00 PM workday on each side, your working-hours overlap window is 10.5:00 am–5:00 pm ist (9:00 am–3.5:00 pm gst). To visualize this instantly for any pair of cities, use the visual meeting planner or the timezone overlap finder — both highlight the green overlap window on a live timeline.

Does IST observe Daylight Saving Time?

India Standard Time (IST) is based on the Asia/Kolkata IANA timezone. DST observance depends on the jurisdiction — for example, most of the continental US switches between standard and daylight time, while India, Japan, and most of Southeast Asia do not observe DST at all. WorldClock.lol uses the authoritative IANA timezone database, so every conversion automatically accounts for the correct DST rules on the date you're converting.

When is 9 AM IST in GST?

When it is 9:00 AM in India Standard Time (IST, UTC+5:30), it is 7.5:00 AM in Gulf Standard Time (GST). For other times of day, scan the conversion table above or drop into the interactive converter to pick an exact minute. The converter handles both standard and daylight variants correctly.

How to Use This IST to GST Converter

1. Type or drag any time in the IST input above — the GST equivalent updates instantly.
2. Check the day indicator. When the converted time crosses midnight, the tool shows +1 day or −1 day so you don't book a meeting on the wrong date.
3. Copy the shareable URL to send the specific conversion to a colleague — the link preserves your exact selection.
4. Switch directions by swapping the input zones, or open GST to IST for the reverse.

Related IST Converters

• IST to EST
• IST to PST
• IST to GMT
• IST to UTC
• IST to JST
• IST to CET

Related GST Converters

• EST to GST
• PST to GST
• GMT to GST
• UTC to GST
• JST to GST
• CET to GST

More Time Tools

• All Time Zone Converters — browse every supported pair
• About IST (India Standard Time) — current time, cities, DST rules
• About GST (Gulf Standard Time) — current time, cities, DST rules
• Meeting Planner — find the best time for a multi-city meeting
• Best Time to Call — optimal calling windows between any two cities
• UTC Time Now — the reference point for every conversion
• DST Schedule 2026 — every daylight-saving transition this year