Convert CET to IRST
IRST is 2 hours 30 minutes ahead of CET. CET is UTC+1 and IRST is UTC+3:30.
Right now: CET · IRST
Best time to schedule a meeting
Standard 9–5 working hours overlap for 6 hours: 9:00 AM–3:00 PM CET (11:00 AM–5:00 PM IRST). Schedule meetings inside that window.
| CET | IRST | Suitable? |
|---|---|---|
| 9:00 AM | 11:30 AM | working hours |
| 10:00 AM | 12:30 PM | working hours |
| 11:00 AM | 1:30 PM | working hours |
| 12:00 PM | 2:30 PM | working hours |
| 1:00 PM | 3:30 PM | working hours |
| 2:00 PM | 4:30 PM | working hours |
| 3:00 PM | 5:30 PM | outside 9–5 |
| 4:00 PM | 6:30 PM | outside 9–5 |
| 5:00 PM | 7:30 PM | outside 9–5 |
CET to IRST conversion table
| CET | IRST |
|---|---|
| 12:00 AM | 2:30 AM |
| 1:00 AM | 3:30 AM |
| 2:00 AM | 4:30 AM |
| 3:00 AM | 5:30 AM |
| 4:00 AM | 6:30 AM |
| 5:00 AM | 7:30 AM |
| 6:00 AM | 8:30 AM |
| 7:00 AM | 9:30 AM |
| 8:00 AM | 10:30 AM |
| 9:00 AM | 11:30 AM |
| 10:00 AM | 12:30 PM |
| 11:00 AM | 1:30 PM |
| 12:00 PM | 2:30 PM |
| 1:00 PM | 3:30 PM |
| 2:00 PM | 4:30 PM |
| 3:00 PM | 5:30 PM |
| 4:00 PM | 6:30 PM |
| 5:00 PM | 7:30 PM |
| 6:00 PM | 8:30 PM |
| 7:00 PM | 9:30 PM |
| 8:00 PM | 10:30 PM |
| 9:00 PM | 11:30 PM |
| 10:00 PM | 12:30 AM (next day) |
| 11:00 PM | 1:30 AM (next day) |
About CET
Central European Time (CET) is UTC+1. It is used in Paris, Berlin, Madrid, Rome and Warsaw in winter.
Central European Time is UTC+1 and covers most of continental Europe in winter — Paris, Berlin, Madrid, Rome, Warsaw. It is worth noting how much of the continent this is: Spain sits geographically west of Britain but runs an hour ahead of it, a legacy of a 1940 decision that was never reversed. From late March to late October the same countries are on CEST, UTC+2.
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?
This gap is seasonal. The abbreviations themselves are fixed offsets, but the region on CET switches to CEST (UTC+2) from late March to late October. So the 2.5-hour figure on this page is correct for the part of the year when both places are actually on these abbreviations, and changes by an hour outside it.
IRST does not shift, so the whole change comes from one side. A recurring meeting fixed in IRST will appear to move by an hour for everyone on the other side, twice a year, without anyone changing anything.
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 CET in IRST?
9:00 AM CET is 11:30 AM IRST.
Is IRST ahead of CET?
IRST is 2 hours 30 minutes ahead of CET.
Which time zone does this use?
CET is UTC+1 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.