IRST to Beijing
+4h 30mIRST
IRSTSOURCEBeijing
CSTGreen rows indicate typical business hours (9 AM - 5 PM)
IRST and CST on the World Map
The map below highlights the IRST (Iran Standard Time) and CST (China 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.
CST – China Standard Time
UTC+08:00China Standard Time (CST) covers all of mainland China, 8 hours ahead of UTC.
- •China uses a single time zone despite spanning 5 geographical zones.
- •In Xinjiang (western China), sunset can be as late as midnight in summer.
- •China abolished daylight saving time in 1991.
- •The Shanghai Stock Exchange operates on CST/Beijing Time.
Understanding the +4h 30m Gap: IRST vs Beijing
IRST runs on Iran Standard Time (IRST) at UTC+03:30. Beijing runs on China Standard Time (CST) at UTC+08:00. That puts IRST 4 hours 30 minutes ahead of Beijing — a difference of +4h 30m at the current offsets.
In practice, when it is 9:00 AM in IRST it is 1:30 PM in Beijing. Midnight in IRST is 4:30 AM in Beijing. Neither zone observes daylight saving time, so the offset between them stays constant all year.
IRST to Beijing time conversion table
| IRST (IRST) | Beijing (CST) | 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 IRST to Beijing time
- Scheduling a call from IRST to Beijing: a 10:00 AM start in IRST lands at 2:30 PM in Beijing, so you can confirm the slot without doing the arithmetic yourself.
- Finding shared working hours: both IRST and Beijing are inside the 9-to-5 working day between 9:00 AM and 12:30 PM IRST time (1:30 PM–5:00 PM CST). That is roughly 3 hours 30 minutes of usable overlap.
- Watching a live event or market open: IRST viewers need 1:30 PM in Beijing to catch a 9:00 AM start there, and 7:30 PM if the event is anchored to IRST.
- 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 IRST and need Beijing 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 CST (China Standard Time)
China Standard Time (CST, also known as Beijing Time) is used across all of mainland China despite the country spanning five geographical time zones. This single-timezone policy was adopted in 1949. China does not observe daylight saving time. CST is shared with Hong Kong (HKT), Macau, Taiwan, Singapore, Malaysia, and the Philippines, making UTC+08:00 one of the most used offsets in the world.
Best time to call between IRST and Beijing
Both IRST and Beijing 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 CST. That gives roughly 3 hours and 30 minutes of shared time — the safest window for a live call or meeting.
Business hours overlap
IRST and Beijing overlap for about 3 hours during the working day — enough for meetings if you avoid the edges of the window.
IRST is 4 hours 30 minutes ahead of Beijing (IRST UTC+03:30 → CST 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 IRST and Beijing?
IRST (IRST, UTC+03:30) is 4 hours 30 minutes ahead of Beijing (CST, UTC+08:00). The gap is currently +4h 30m.
How do I convert IRST time to Beijing time?
Add +4h 30m to IRST local time. For example, 9:00 AM in IRST is 1:30 PM in Beijing.
What time is it in Beijing right now?
Beijing uses CST 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 IRST.
What is the best time to call Beijing from IRST?
Call between 9:00 AM and 12:30 PM IRST — that maps to 1:30 PM–5:00 PM CST and keeps both parties inside the working day.
Which is ahead, IRST or Beijing?
IRST is 4 hours 30 minutes ahead of Beijing. When it is 12:00 PM in IRST it is 4:30 PM in Beijing.
Do IRST and Beijing use different time zones?
IRST uses IRST at UTC+03:30, while Beijing (China) uses CST at UTC+08:00. The IANA identifiers are Asia/Tehran and Asia/Shanghai.
Does daylight saving time affect the IRST–Beijing difference?
Neither zone observes daylight saving time, so the +4h 30m offset between IRST and Beijing 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 Beijing?
Not normally. The +4h 30m gap only pushes the date over for late-evening times.
What is the time difference between IRST and Beijing?
Beijing is +4h 30m from IRST.
What timezone is IRST in?
IRST operates on its local timezone.
What timezone is Beijing in?
Beijing 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 CST timezone?
Major cities in the CST timezone include Shanghai, Beijing, Shenzhen, Guangzhou, Chengdu, Hong Kong, Taipei, Wuhan.
What is the UTC offset for CST?
China Standard Time (CST) is at UTC+08:00.
What should I know about the CST timezone?
China uses a single time zone despite spanning 5 geographical zones. In Xinjiang (western China), sunset can be as late as midnight in summer.
When is it midnight in IRST, what time is it in Beijing?
When it is 12:00 AM (midnight) in IRST (IRST), it is +4h 30m later in Beijing (CST).
Related Developer Tools
Explore more tools that work great with timezone conversions for international teams:
Related Timezone Conversions
More IRST time conversions
- irst to tehran
- irst to iran
- irst to new york
- irst to london
- irst to dubai
- irst to tokyo
- irst to singapore
- irst to sydney
- irst to los angeles
- irst to paris
- irst to delhi
- irst to mumbai
- irst to berlin
- irst to hong kong
- irst to toronto
- irst to kathmandu
- new york to irst
- london to irst
- dubai to irst
- tokyo to irst
- singapore to irst
- sydney to irst
- los angeles to irst
- paris to irst
- delhi to irst
- mumbai to irst
- berlin to irst
- hong kong to irst
- toronto to irst
- kathmandu to irst
See every conversion from IRST →·See every conversion from Beijing →