Updating current time…
UTC
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IRST
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Quick answers

Selected conversion

12:00 pm12:00 UTC (UTC+0), Oct 13, 2026 = 3:30 pm15:30 IRST (UTC+3:30), Oct 13, 2026

UTC is 3 hours and 30 minutes behind IRST.

UTC and IRST examples

These examples always use UTC (UTC+0) 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.

UTC is 3 hours and 30 minutes behind IRST.

How the time difference changes

UTC is 3 hours and 30 minutes behind IRST year-round.

Working hours of 9:00 am to 5:00 pm in UTC correspond to 12:30 pm to 8:30 pm in IRST.Working hours of 09:00 to 17:00 in UTC correspond to 12:30 to 20:30 in IRST.

Compare UTC time with IRST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.

Time Difference

Coordinated Universal Time is 3 hours and 30 minutes behind Iran Standard Time.
12:00 pm12:00 in UTC is 3:30 pm15:30 in IRST

UTC to IRST call time
Best time for a conference call or a meeting is between 9am-1:30pm09:00-13:30 in UTC which corresponds to 12:30pm-5pm12:30-17:00 in IRST

12:00 pm12:00 Coordinated Universal Time (UTC). Offset UTC 0:00 hours
3:30 pm15:30 Iran Standard Time (IRST). Offset UTC +3:30 hours

12:00 pm12:00 UTC / 3:30 pm15:30 IRST

Choose an hour to update the converter. Day labels such as “next day” or “+1” are relative to the selected date in the first column. Use Up and Down arrow keys, Home or End to move between hours, then Enter or Space to select.

Hourly time comparison
UTCIRST
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Coordinated Universal Time

Offset: UTC is the same as Greenwich Mean Time (GMT).

Coordinated Universal Time (UTC) is the world time standard that regulates clocks and time. It is the successor to Greenwich Mean Time (GMT). For casual use, UTC is the same as GMT, but UTC is the standard the scientific community uses.
UTC has been the time standard commonly used across the world since 1972. It is used in many technical fields, such as aviation and meteorology, and to synchronize time across internet networks.

Map of the areas on Coordinated Universal Time (UTC)
UTC all year UTC part of the year

Today some of the lighter areas are on UTC+1 (British Summer Time, Irish Standard Time, WEST).

UTC representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • Z - is the zone designator for the zero UTC/GMT offset, also known as 'Zulu' time
  • +00 - basic short
  • +0000 - basic
  • +00:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0000 - sign character (+) followed by a four digit time providing hours (00) and minutes (00) of the offset. Indicates the zero UTC/GMT offset.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Zulu - Military abbreviation for UTC
  • Z - short form of 'Zulu'
IANA/Olson: Reflects UTC time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Etc/UCT
  • Etc/UTC
  • Etc/Universal
  • Etc/Zulu
  • UCT
  • UTC
  • Universal
  • Zulu
Time zones with the GMT +0 offset:
  • EGST - Eastern Greenland Summer Time
  • GMT - Greenwich Mean Time
  • WET - Western European Time
  • AZOST - Azores Summer Time
  • UTC - Coordinated Universal Time
  • WT - Western Sahara Standard Time
  • Z - Zulu Time Zone

Iran Standard Time

Offset: IRST is 3 hours and 30 minutes ahead of Greenwich Mean Time (GMT).

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; see upcoming clock changes worldwide.

IRST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +0330 - basic
  • +03:30 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +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.