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Convert ICT to IRST

IRST is 3 hours 30 minutes behind ICT. ICT is UTC+7 and IRST is UTC+3:30.

Right now: ICT · IRST

Best time to schedule a meeting

Standard 9–5 working hours overlap for 4 hours: 1:00 PM–5:00 PM ICT (9:00 AM–1:00 PM IRST). Schedule meetings inside that window.

ICTIRSTSuitable?
9:00 AM5:30 AMoutside 9–5
10:00 AM6:30 AMoutside 9–5
11:00 AM7:30 AMoutside 9–5
12:00 PM8:30 AMoutside 9–5
1:00 PM9:30 AMworking hours
2:00 PM10:30 AMworking hours
3:00 PM11:30 AMworking hours
4:00 PM12:30 PMworking hours
5:00 PM1:30 PMworking hours

ICT to IRST conversion table

ICTIRST
12:00 AM8:30 PM (previous day)
1:00 AM9:30 PM (previous day)
2:00 AM10:30 PM (previous day)
3:00 AM11:30 PM (previous day)
4:00 AM12:30 AM
5:00 AM1:30 AM
6:00 AM2:30 AM
7:00 AM3:30 AM
8:00 AM4:30 AM
9:00 AM5:30 AM
10:00 AM6:30 AM
11:00 AM7:30 AM
12:00 PM8:30 AM
1:00 PM9:30 AM
2:00 PM10:30 AM
3:00 PM11:30 AM
4:00 PM12:30 PM
5:00 PM1:30 PM
6:00 PM2:30 PM
7:00 PM3:30 PM
8:00 PM4:30 PM
9:00 PM5:30 PM
10:00 PM6:30 PM
11:00 PM7:30 PM

About ICT

Indochina Time (ICT) is UTC+7. It is used in Bangkok, Hanoi, Ho Chi Minh City and Jakarta.

Indochina Time is UTC+7, covering Thailand, Vietnam, Cambodia and Laos, with no daylight saving in any of them. Bangkok and Hanoi keep the same clock, which makes the region unusually simple to schedule across — the complication is only ever with the countries around it, since Myanmar is at UTC+6:30 and Malaysia at UTC+8.

About IRST

Iran Standard Time (IRST) is UTC+3:30. It is used in Iran, all year.

Iran Standard Time is UTC+3:30. Iran ran daylight saving for decades and stopped in 2022, so material written before then puts the country half an hour further ahead in summer and is now wrong. Half-hour offsets are rare enough that scheduling tools sometimes round them, which turns a correct calculation into a thirty-minute error.

Does this gap change with the seasons?

Neither ICT nor IRST shifts with the seasons, so this 3.5-hour difference holds all year. That is unusual enough to be worth relying on: most cross-continental gaps move twice a year.

This is the reason scheduling systems store an IANA zone such as Region/City rather than an offset or an abbreviation: the zone knows its own rules and the offset does not.

Frequently asked questions

What time is 9:00 AM ICT in IRST?

9:00 AM ICT is 5:30 AM IRST.

Is IRST ahead of ICT?

IRST is 3 hours 30 minutes behind ICT.

Which time zone does this use?

ICT is UTC+7 and IRST is UTC+3:30. Both abbreviations denote a single fixed offset, so this conversion never shifts with daylight saving — what changes is which abbreviation a place is using at the time.

Other ICT conversions

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