IRST to NST
-7hIRST
IRSTSOURCENST
NSTGreen rows indicate typical business hours (9 AM - 5 PM)
IRST and NST on the World Map
The map below highlights the IRST (Iran Standard Time) and NST (Newfoundland Standard Time) timezone regions across the globe.
IRST – Iran Standard Time
UTC+03:30Iran Standard Time (IRST) is the time zone for Iran, 3 hours and 30 minutes ahead of UTC.
- •IRST is one of only a few time zones with a 30-minute offset.
- •Iran observes daylight saving time, switching to IRDT (UTC+04:30).
- •Tehran has a metropolitan population of over 16 million.
NST – Newfoundland Standard Time
UTC-03:30Newfoundland Standard Time (NST) is a unique half-hour offset time zone in Canada, 3.5 hours behind UTC.
- •NST is one of only a few half-hour offset time zones in the world.
- •Newfoundland joined Canada in 1949 and kept its unique time zone.
- •St. John's is the easternmost city in North America.
IRST to NST Time Difference – Complete Guide
IRST runs on Iran Standard Time (IRST) at UTC+03:30. NST runs on Newfoundland Standard Time (NST) at UTC-03:30. That puts IRST 7 hours behind NST — a difference of -7h at the current offsets.
In practice, when it is 9:00 AM in IRST it is 2:00 AM in NST. Midnight in IRST is 5:00 PM in NST. Neither zone observes daylight saving time, so the offset between them stays constant all year.
IRST to NST time conversion table
| IRST (IRST) | NST (NST) | Day |
|---|---|---|
| 12:00 AM | 5:00 PM | previous day |
| 6:00 AM | 11:00 PM | previous day |
| 7:00 AM | 12:00 AM | same day |
| 8:00 AM | 1:00 AM | same day |
| 9:00 AM | 2:00 AM | same day |
| 12:00 PM | 5:00 AM | same day |
| 3:00 PM | 8:00 AM | same day |
| 5:00 PM | 10:00 AM | same day |
| 6:00 PM | 11:00 AM | same day |
| 9:00 PM | 2:00 PM | same day |
Why people convert IRST to NST time
- Scheduling a call from IRST to NST: a 10:00 AM start in IRST lands at 3:00 AM in NST, so you can confirm the slot without doing the arithmetic yourself.
- Finding shared working hours: both IRST and NST are inside the 9-to-5 working day between 4:00 PM and 5:00 PM IRST time (9:00 AM–10:00 AM NST). That is roughly 1 hours of usable overlap.
- Booking travel or deliveries: tracking NST local time against IRST keeps pickup windows and arrival estimates honest across the -7h offset.
- Always state the zone abbreviation, not just the hour. "3:00 PM IRST" is unambiguous; "3 PM" across a -7h gap is not.
- Block 4:00 PM–5:00 PM IRST as the recurring meeting window if you work primarily from IRST and need NST colleagues present.
About IRST (Iran Standard Time)
Iran Standard Time (IRST) is one of the few time zones with a 30-minute offset. Iran observes daylight saving time (IRDT, UTC+04:30) from late March to late September. Tehran, the capital, is one of the largest cities in the Middle East.
About NST (Newfoundland Standard Time)
Newfoundland Standard Time (NST) is one of the few half-hour offset time zones in the world. It covers the island of Newfoundland in Canada and is 30 minutes ahead of Atlantic Standard Time. This unique offset exists because Newfoundland was an independent country until 1949.
Best time to call between IRST and NST
Both IRST and NST sit inside the 9 AM – 5 PM working day between 4:00 PM–5:00 PM IRST, which is 9:00 AM–10:00 AM NST. That gives roughly 1 hours of shared time — the safest window for a live call or meeting.
Business hours overlap
IRST and NST overlap for only 60 minutes (4:00 PM–5:00 PM IRST), so meetings have to be booked precisely.
IRST is 7 hours behind NST (IRST UTC+03:30 → NST UTC-03:30). The shared working window is 4:00 PM–5:00 PM IRST. Remember to re-check around daylight-saving transitions.
🕐 Daylight Saving Time Info
IRST
Does not observe DST
NST
☀ Currently in DST
Standard: UTC-03:30 · DST: UTC-02:30
Clocks fall back on Sun, Nov 1, 2026
Learn More About Time
Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:
Frequently Asked Questions
What is the time difference between IRST and NST?
IRST (IRST, UTC+03:30) is 7 hours behind NST (NST, UTC-03:30). The gap is currently -7h.
How do I convert IRST time to NST time?
Add -7h to IRST local time. For example, 9:00 AM in IRST is 2:00 AM in NST.
What time is it in NST right now?
NST uses NST at UTC-03:30. Use the live converter at the top of this page — it updates in real time and already accounts for the -7h offset from IRST.
What is the best time to call NST from IRST?
Call between 4:00 PM and 5:00 PM IRST — that maps to 9:00 AM–10:00 AM NST and keeps both parties inside the working day.
Which is behind, IRST or NST?
IRST is 7 hours behind NST. When it is 12:00 PM in IRST it is 5:00 AM in NST.
Does daylight saving time affect the IRST–NST difference?
Neither zone observes daylight saving time, so the -7h offset between IRST and NST is fixed all year.
Which other cities share IRST's time zone?
IRST also covers Tehran, Isfahan, Mashhad, Tabriz, Shiraz, Karaj.
Which countries use IRST, IRST's zone?
IRST is used in Iran.
Is there a day difference between IRST and NST?
Not normally. The -7h gap only pushes the date over the previous day.
What is the time difference between IRST and NST?
NST is -7h from IRST.
What timezone is IRST in?
IRST operates on its local timezone.
What timezone is NST in?
NST operates on its local timezone.
Which countries use IRST (Iran Standard Time)?
IRST is used in Iran.
Does IRST observe daylight saving time?
Yes, IRST switches to IRDT during summer months.
What are some interesting facts about IRST?
IRST is one of only a few time zones with a 30-minute offset. Iran observes daylight saving time, switching to IRDT (UTC+04:30).
Which cities are in the NST timezone?
Major cities in the NST timezone include St. John's, Corner Brook, Mount Pearl.
What is the UTC offset for NST?
Newfoundland Standard Time (NST) is at UTC-03:30. During daylight saving time, it shifts to NDT.
What should I know about the NST timezone?
NST is one of only a few half-hour offset time zones in the world. Newfoundland joined Canada in 1949 and kept its unique time zone.
When is it midnight in IRST, what time is it in NST?
When it is 12:00 AM (midnight) in IRST (IRST), it is -7h later in NST (NST).
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