GST to IRST Converter
Quick answers
Selected conversion
The selected date and time will appear here when the converter loads.
GST and IRST examples
These examples always use GST (UTC+4) and IRST (UTC+3:30). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.
GST is 30 minutes ahead of IRST.
How the time difference changes
GST is 30 minutes ahead of IRST year-round.
Working hours of 9:00 am to 5:00 pm in GST correspond to 8:30 am to 4:30 pm in IRST.
Compare GST time with IRST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Gulf Standard Time is 0 hours and 30 minutes ahead of Iran Standard Time
4:00 pm16:00 in GST is 3:30 pm15:30 in IRST
GST to IRST call time
Best time for a conference call or a meeting is between 9:30am-5pm in GST which corresponds to 9am-4:30pm in IRST
4:00 pm16:00 Gulf Standard Time (GST). Offset UTC +4:00 hours
3:30 pm15:30 Iran Standard Time (IRST). Offset UTC +3:30 hours
4:00 pm16:00 GST / 3:30 pm15:30 IRST
| GST | IRST |
|---|---|
| 12am (midnight) | 11:30 pm |
| 1am | 12:30 am |
| 2am | 1:30 am |
| 3am | 2:30 am |
| 4am | 3:30 am |
| 5am | 4:30 am |
| 6am | 5:30 am |
| 7am | 6:30 am |
| 8am | 7:30 am |
| 9am | 8:30 am |
| 10am | 9:30 am |
| 11am | 10:30 am |
| 12pm (noon) | 11:30 am |
| 1pm | 12:30 pm |
| 2pm | 1:30 pm |
| 3pm | 2:30 pm |
| 4pm | 3:30 pm |
| 5pm | 4:30 pm |
| 6pm | 5:30 pm |
| 7pm | 6:30 pm |
| 8pm | 7:30 pm |
| 9pm | 8:30 pm |
| 10pm | 9:30 pm |
| 11pm | 10:30 pm |
| 00:00 | 23:30 |
| 01:00 | 00:30 |
| 02:00 | 01:30 |
| 03:00 | 02:30 |
| 04:00 | 03:30 |
| 05:00 | 04:30 |
| 06:00 | 05:30 |
| 07:00 | 06:30 |
| 08:00 | 07:30 |
| 09:00 | 08:30 |
| 10:00 | 09:30 |
| 11:00 | 10:30 |
| 12:00 | 11:30 |
| 13:00 | 12:30 |
| 14:00 | 13:30 |
| 15:00 | 14:30 |
| 16:00 | 15:30 |
| 17:00 | 16:30 |
| 18:00 | 17:30 |
| 19:00 | 18:30 |
| 20:00 | 19:30 |
| 21:00 | 20:30 |
| 22:00 | 21:30 |
| 23:00 | 22:30 |
Gulf Standard Time
Offset: GST is 4 hours ahead Greenwich Mean Time (GMT) and is used in Asia
Countries using this time zone: United Arab Emirates
Principal Cities: The largest city in the GST time zone is Dubai in United Arab Emirates, with about 1.137 million people. Other major cities in this time zone include Abu Dhabi, Sharjah, Al Ain, Ajman.
Daylight Saving: Clocks in Gulf Standard Time (GST) do not change for daylight saving time, so GST stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter.

GST representations, usage and related time zones
- +04 - basic short
- +0400 - basic
- +04:00 - extended
- +0400 - sign character (+) followed by a four digit time providing hours (04) and minutes (00) of the offset. Indicates an offset of four hours to the east of the zero meridian.
- Delta - Military abbreviation for GST
- D - short form of 'Delta'
- KUYT - Kuybyshev Time
- MSD - Moscow Daylight Time
- SAMT - Samara Time
- AMT - Armenia Time
- AZT - Azerbaijan Time
- D - Delta Time Zone
- GET - Georgia Standard Time
- GST - Gulf Standard Time
- MUT - Mauritius Time
- RET - Reunion Time
- SCT - Seychelles Time
Iran Standard Time
Offset: IRST is 3 hours and 30 minutes ahead Greenwich Mean Time (GMT) and is used in Asia
Countries using this time zone: Iran
Principal Cities: The largest city in the IRST time zone is Tehran in Iran, with about 7.153 million people. Other major cities in this time zone include Mashhad, Isfahan, Karaj, Tabriz.
Daylight Saving: Clocks in Iran Standard Time (IRST) do not change for daylight saving time, so IRST stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter.

IRST representations, usage and related time zones
- +0330 - basic
- +03:30 - extended
- +0330 - sign character (+) followed by a four digit time providing hours (03) and minutes (30) of the offset. Indicates an offset of three hours and thirty minutes to the east of the zero meridian.
