Convert NZST to IRST
IRST is 8 hours 30 minutes behind NZST. NZST is UTC+12 and IRST is UTC+3:30.
Right now: NZST · IRST
Best time to schedule a meeting
Standard 9–5 working hours do not overlap at all between NZST and IRST. Someone has to take an early or late call — or use asynchronous communication instead.
| NZST | IRST | Suitable? |
|---|---|---|
| 9:00 AM | 12:30 AM | outside 9–5 |
| 10:00 AM | 1:30 AM | outside 9–5 |
| 11:00 AM | 2:30 AM | outside 9–5 |
| 12:00 PM | 3:30 AM | outside 9–5 |
| 1:00 PM | 4:30 AM | outside 9–5 |
| 2:00 PM | 5:30 AM | outside 9–5 |
| 3:00 PM | 6:30 AM | outside 9–5 |
| 4:00 PM | 7:30 AM | outside 9–5 |
| 5:00 PM | 8:30 AM | outside 9–5 |
NZST to IRST conversion table
| NZST | IRST |
|---|---|
| 12:00 AM | 3:30 PM (previous day) |
| 1:00 AM | 4:30 PM (previous day) |
| 2:00 AM | 5:30 PM (previous day) |
| 3:00 AM | 6:30 PM (previous day) |
| 4:00 AM | 7:30 PM (previous day) |
| 5:00 AM | 8:30 PM (previous day) |
| 6:00 AM | 9:30 PM (previous day) |
| 7:00 AM | 10:30 PM (previous day) |
| 8:00 AM | 11:30 PM (previous day) |
| 9:00 AM | 12:30 AM |
| 10:00 AM | 1:30 AM |
| 11:00 AM | 2:30 AM |
| 12:00 PM | 3:30 AM |
| 1:00 PM | 4:30 AM |
| 2:00 PM | 5:30 AM |
| 3:00 PM | 6:30 AM |
| 4:00 PM | 7:30 AM |
| 5:00 PM | 8:30 AM |
| 6:00 PM | 9:30 AM |
| 7:00 PM | 10:30 AM |
| 8:00 PM | 11:30 AM |
| 9:00 PM | 12:30 PM |
| 10:00 PM | 1:30 PM |
| 11:00 PM | 2:30 PM |
About NZST
New Zealand Standard Time (NZST) is UTC+12. It is used in Auckland and Wellington in the southern winter.
New Zealand Standard Time is UTC+12, the furthest ahead of the commonly used abbreviations, moving to NZDT at UTC+13 from late September to early April. New Zealand is where the date changes first for most of the world's working population, which is why release schedules and financial rollovers are often expressed relative to it. Chatham Islands time, at UTC+12:45, is one of only three quarter-hour offsets in use anywhere.
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 NZST nor IRST shifts with the seasons, so this 8.5-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 NZST in IRST?
9:00 AM NZST is 12:30 AM IRST.
Is IRST ahead of NZST?
IRST is 8 hours 30 minutes behind NZST.
Which time zone does this use?
NZST is UTC+12 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.