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GST
Gulf Standard Time
GMT +4
12am
3am
6am
9am
12pm
3pm
6pm
9pm
IRST/IRDT
Iran Standard Time
GMT +3:30
12am
3am
6am
9am
12pm
3pm
6pm
9pm
IRDT is not used on this date
This converter uses IRST (GMT +3:30), the offset Tehran uses on this date. Open the IRST converter.

Quick answers

Selected conversion

The selected date and time will appear here when the converter loads.

GST and IRDT examples

These examples always use GST (UTC+4) and IRDT (UTC+4:30). 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 behind IRDT.

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 IRDT 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

GSTIRST
12am (midnight)11:30 pm
1am12:30 am
2am1:30 am
3am2:30 am
4am3:30 am
5am4:30 am
6am5:30 am
7am6:30 am
8am7:30 am
9am8:30 am
10am9:30 am
11am10:30 am
12pm (noon)11:30 am
1pm12:30 pm
2pm1:30 pm
3pm2:30 pm
4pm3:30 pm
5pm4:30 pm
6pm5:30 pm
7pm6:30 pm
8pm7:30 pm
9pm8:30 pm
10pm9:30 pm
11pm10:30 pm
00:0023:30
01:0000:30
02:0001:30
03:0002:30
04:0003:30
05:0004:30
06:0005:30
07:0006:30
08:0007:30
09:0008:30
10:0009:30
11:0010:30
12:0011:30
13:0012:30
14:0013:30
15:0014:30
16:0015:30
17:0016:30
18:0017:30
19:0018:30
20:0019:30
21:0020:30
22:0021:30
23:0022:30

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 3.79 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 Time Zone Geo Map
GST timezone map

GST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +04 - basic short
  • +0400 - basic
  • +04:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +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.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Delta - Military abbreviation for GST
  • D - short form of 'Delta'
Time zones with the GMT +4 offset:
  • 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 Daylight Time

Offset: IRDT is 4 hours and 30 minutes ahead Greenwich Mean Time (GMT) and is used in Asia

IRDT Time Zone Geo Map
IRDT timezone map

IRDT representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +0430 - basic
  • +04:30 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0430 - sign character (+) followed by a four digit time providing hours (04) and minutes (30) of the offset. Indicates an offset of four hours and thirty minutes to the east of the zero meridian.
Time zones with the GMT +4:30 offset:
  • AFT - Afghanistan Time
  • IRDT - Iran Daylight Time