Tehran to HKT
+4h 30mTehran
IRSTSOURCEHKT
HKTGreen rows indicate typical business hours (9 AM - 5 PM)
IRST and HKT on the World Map
The map below highlights the IRST (Iran Standard Time) and HKT (Hong Kong 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.
HKT – Hong Kong Time
UTC+08:00Hong Kong Time (HKT, UTC+08:00) is the time zone for Hong Kong, 8 hours ahead of UTC.
- •Hong Kong does not observe daylight saving time and has kept UTC+08:00 since 1979.
- •HKT shares its offset with China Standard Time, Singapore Time and Philippine Time.
- •The Hong Kong Stock Exchange opens at 09:30 HKT.
- •Hong Kong Time does not change with the seasons, so its gap to other zones is fixed.
About Tehran
WikipediaTehran operates on Iran Standard Time (IRST), UTC+3:30. Iran's unique half-hour offset makes Tehran time distinctive for regional business coordination.
Iran Standard Time (IRST) is one of few timezones with a 30-minute offset (UTC+3:30).
Everything You Need to Know About Tehran and HKT Time
Tehran runs on Iran Standard Time (IRST) at UTC+03:30. HKT runs on Hong Kong Time (HKT) at UTC+08:00. That puts Tehran 4 hours 30 minutes ahead of HKT — a difference of +4h 30m at the current offsets.
In practice, when it is 9:00 AM in Tehran it is 1:30 PM in HKT. Midnight in Tehran is 4:30 AM in HKT. Neither zone observes daylight saving time, so the offset between them stays constant all year.
Tehran to HKT time conversion table
| Tehran (IRST) | HKT (HKT) | Day |
|---|---|---|
| 12:00 AM | 4:30 AM | same day |
| 6:00 AM | 10:30 AM | same day |
| 7:00 AM | 11:30 AM | same day |
| 8:00 AM | 12:30 PM | same day |
| 9:00 AM | 1:30 PM | same day |
| 12:00 PM | 4:30 PM | same day |
| 3:00 PM | 7:30 PM | same day |
| 5:00 PM | 9:30 PM | same day |
| 6:00 PM | 10:30 PM | same day |
| 9:00 PM | 1:30 AM | next day |
Why people convert Tehran to HKT time
- Scheduling a call from Tehran to HKT: a 10:00 AM start in Tehran lands at 2:30 PM in HKT, so you can confirm the slot without doing the arithmetic yourself.
- Finding shared working hours: both Tehran and HKT are inside the 9-to-5 working day between 9:00 AM and 12:30 PM IRST time (1:30 PM–5:00 PM HKT). That is roughly 3 hours 30 minutes of usable overlap.
- Keeping family and friends in sync: knowing that 8:00 PM in Tehran is 12:30 AM in HKT makes it easy to avoid calling at 3 AM.
- Always state the zone abbreviation, not just the hour. "3:00 PM IRST" is unambiguous; "3 PM" across a +4h 30m gap is not.
- Block 9:00 AM–12:30 PM IRST as the recurring meeting window if you work primarily from Tehran and need HKT 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 HKT (Hong Kong Time)
Hong Kong Time (HKT) is fixed at UTC+08:00 all year and does not observe daylight saving time. Hong Kong last used summer time in 1979 and has kept a single offset since. HKT shares the UTC+08:00 offset with China Standard Time, Singapore Time, Malaysian Time, Philippine Time and Australian Western Standard Time, but is listed separately because Hong Kong maintains its own timekeeping authority. As a major financial centre, Hong Kong's trading hours set the rhythm for markets across Asia, opening at 09:30 HKT which is 01:30 in London and 20:30 the previous evening in New York.
Best time to call between Tehran and HKT
Both Tehran and HKT sit inside the 9 AM – 5 PM working day between 9:00 AM–12:30 PM IRST, which is 1:30 PM–5:00 PM HKT. That gives roughly 3 hours and 30 minutes of shared time — the safest window for a live call or meeting.
Business hours overlap
Tehran and HKT overlap for about 3 hours during the working day — enough for meetings if you avoid the edges of the window.
Tehran is 4 hours 30 minutes ahead of HKT (IRST UTC+03:30 → HKT UTC+08:00). The shared working window is 9:00 AM–12:30 PM IRST. Remember to re-check around daylight-saving transitions.
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 Tehran and HKT?
Tehran (IRST, UTC+03:30) is 4 hours 30 minutes ahead of HKT (HKT, UTC+08:00). The gap is currently +4h 30m.
How do I convert Tehran time to HKT time?
Add +4h 30m to Tehran local time. For example, 9:00 AM in Tehran is 1:30 PM in HKT.
What time is it in HKT right now?
HKT uses HKT at UTC+08:00. Use the live converter at the top of this page — it updates in real time and already accounts for the +4h 30m offset from Tehran.
What is the best time to call HKT from Tehran?
Call between 9:00 AM and 12:30 PM IRST — that maps to 1:30 PM–5:00 PM HKT and keeps both parties inside the working day.
Which is ahead, Tehran or HKT?
Tehran is 4 hours 30 minutes ahead of HKT. When it is 12:00 PM in Tehran it is 4:30 PM in HKT.
Do Tehran and HKT use different time zones?
Tehran (Iran) uses IRST at UTC+03:30, while HKT uses HKT at UTC+08:00. The IANA identifiers are Asia/Tehran and Asia/Hong_Kong.
Does daylight saving time affect the Tehran–HKT difference?
Neither zone observes daylight saving time, so the +4h 30m offset between Tehran and HKT is fixed all year.
Which other cities share Tehran's time zone?
IRST also covers Tehran, Isfahan, Mashhad, Tabriz, Shiraz, Karaj.
Which countries use IRST, Tehran's zone?
IRST is used in Iran.
Is there a day difference between Tehran and HKT?
Not normally. The +4h 30m gap only pushes the date over for late-evening times.
What is the time difference between Tehran and HKT?
HKT is +4h 30m from Tehran.
What timezone is Tehran in?
Tehran operates on Iran Standard Time (IRST), UTC+3:30. Iran's unique half-hour offset makes Tehran time distinctive for regional business coordination.
What timezone is HKT in?
HKT operates on its local timezone.
What are the business hours in Tehran?
Standard business hours in Tehran are 8:00 AM - 4:00 PM IRST.
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 HKT timezone?
Major cities in the HKT timezone include Hong Kong, Kowloon, Tsuen Wan, Sha Tin.
What is the UTC offset for HKT?
Hong Kong Time (HKT) is at UTC+08:00.
What should I know about the HKT timezone?
Hong Kong does not observe daylight saving time and has kept UTC+08:00 since 1979. HKT shares its offset with China Standard Time, Singapore Time and Philippine Time.
When is it midnight in Tehran, what time is it in HKT?
When it is 12:00 AM (midnight) in Tehran (IRST), it is +4h 30m later in HKT (HKT).
Related Developer Tools
Explore more tools that work great with timezone conversions for international teams:
Related Timezone Conversions
More Tehran time conversions
- tehran to irst
- tehran to iran
- tehran to dubai
- tehran to mumbai
- tehran to delhi
- tehran to bangalore
- tehran to kathmandu
- tehran to bangkok
- tehran to singapore
- tehran to hong kong
- tehran to shanghai
- tehran to beijing
- tehran to tokyo
- tehran to osaka
- tehran to new york
- tehran to london
- tehran to sydney
- tehran to los angeles
- tehran to paris
- tehran to berlin
- tehran to toronto
- new york to tehran
- london to tehran
- dubai to tehran
- tokyo to tehran
- singapore to tehran
- sydney to tehran
- los angeles to tehran
- paris to tehran
- delhi to tehran
- mumbai to tehran
- berlin to tehran
- hong kong to tehran
- toronto to tehran
- kathmandu to tehran
See every conversion from Tehran →·See every conversion from HKT →