GST to IST time converter
Enter a time in GST to get the matching time in IST, whether it falls on the next or previous day, and a full 24-hour table. Handy for planning calls between Dubai and Muscat and Mumbai and New Delhi.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter time in gst and day in gst (optional).
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
IST time = GST time + 1.5 hours, because IST is UTC+5:30 and GST is UTC+4. If the result reaches 24:00 or more, subtract 24 hours and move to the next day; if it drops below 00:00, add 24 hours and move to the previous day.
Example
Inputs: Time in GST = 22:00, Day in GST (optional) = Thursday. Result: Time in IST: 23:30; Day change: Same day (0); Offset difference (IST minus GST): 1.5 hours.
Limits and caveats
- Fixed offsets are used: GST = UTC+4 and IST = UTC+5:30, whatever the date.
- GST here is Gulf Standard Time (UTC+4) of the UAE and Oman.
Questions about this tool
What time is 09:00 GST in IST?
09:00 GST is 10:30 IST on the same day, because IST is 1.5 hours ahead of GST.
Does daylight saving time change the result?
No. The UAE and Oman do not use daylight saving and India does not use daylight saving, so the 1.5 hour gap between GST and IST holds all year.
Which IST does this tool use?
Here IST means India Standard Time, UTC+5:30. The same letters are used for Irish Standard Time (UTC+1, Irish summer time) and Israel Standard Time (UTC+2).