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AST to Beijing

+12h

AST

ASTSOURCE
UTC-03:00☀ DST active
HH12
:
MM00
  
12:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM

Beijing

CST
China · UTC+08:00
HH12
:
MM00
  
(next day)00:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM
AST
Beijing
12:00 AM
11:00 AM
2:00 AM
1:00 PM
4:00 AM
3:00 PM
6:00 AM
5:00 PM
8:00 AM
7:00 PM
10:00 AM
9:00 PM
12:00 PM
11:00 PM
2:00 PM
1:00 AM+1
4:00 PM
3:00 AM+1
6:00 PM
5:00 AM+1
8:00 PM
7:00 AM+1
10:00 PM
9:00 AM+1

Green rows indicate typical business hours (9 AM - 5 PM)

AST and CST on the World Map

The map below highlights the AST (Atlantic Standard Time) and CST (China Standard Time) timezone regions across the globe.

ASTCSTHalifaxSan JuanSanto DomingoCaracasShanghaiBeijingShenzhenGuangzhou
AST Zone
→
CST Zone

Explore all world timezones interactively →

AST – Atlantic Standard Time

UTC-04:00

Atlantic Standard Time (AST) is the time zone for the Canadian Atlantic provinces and the Caribbean, 4 hours behind UTC.

Countries in AST
Canada (Atlantic provinces)Puerto RicoUS Virgin IslandsDominican RepublicVenezuelaBoliviaBarbadosTrinidad and Tobago
Major Cities in AST
HalifaxSan JuanSanto DomingoCaracasLa PazFrederictonCharlottetown
Key Facts about AST
  • •Puerto Rico uses AST year-round and does not observe DST.
  • •AST is 1 hour ahead of EST.
  • •Halifax, the capital of Nova Scotia, is the largest city in AST Canada.
Daylight Saving:Yes – switches to ADT
Learn more about AST on Wikipedia

CST – China Standard Time

UTC+08:00

China Standard Time (CST) covers all of mainland China, 8 hours ahead of UTC.

Countries in CST
ChinaHong KongMacauTaiwan
Major Cities in CST
ShanghaiBeijingShenzhenGuangzhouChengduHong KongTaipeiWuhanHangzhouNanjing
Key Facts about CST
  • •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.
Daylight Saving:No – UTC+08:00 year-round
Learn more about CST on Wikipedia

Understanding the +12h Gap: AST vs Beijing

AST runs on Atlantic Standard Time (AST) at UTC-04:00. Beijing runs on China Standard Time (CST) at UTC+08:00. That puts AST 12 hours ahead of Beijing — a difference of +12h at the current offsets.

In practice, when it is 9:00 AM in AST it is 9:00 PM in Beijing. Midnight in AST is 12:00 PM in Beijing. Neither zone observes daylight saving time, so the offset between them stays constant all year.

AST to Beijing time conversion table

AST (AST)Beijing (CST)Day
12:00 AM12:00 PMsame day
6:00 AM6:00 PMsame day
7:00 AM7:00 PMsame day
8:00 AM8:00 PMsame day
9:00 AM9:00 PMsame day
12:00 PM12:00 AMnext day
3:00 PM3:00 AMnext day
5:00 PM5:00 AMnext day
6:00 PM6:00 AMnext day
9:00 PM9:00 AMnext day

Why people convert AST to Beijing time

  • Scheduling a call from AST to Beijing: a 10:00 AM start in AST lands at 10:00 PM in Beijing, so you can confirm the slot without doing the arithmetic yourself.
  • Handling a +12h gap: AST and Beijing have no overlap inside a normal 9-to-5 day, so real-time meetings need an early-morning or late-evening slot on one side. 9:00 AM in Beijing is 9:00 PM in AST.
  • Watching a live event or market open: AST viewers need 9:00 PM in Beijing to catch a 9:00 AM start there, and 12:00 PM if the event is anchored to AST.
  • Always state the zone abbreviation, not just the hour. "3:00 PM AST" is unambiguous; "3 PM" across a +12h gap is not.
  • With a +12h gap there is no shared 9-to-5 window, so alternate the early start: one week AST takes the early slot, the next week Beijing does.

About AST (Atlantic Standard Time)

Atlantic Standard Time (AST) covers Canada's Atlantic provinces (Nova Scotia, New Brunswick, Prince Edward Island, and most of Labrador), as well as several Caribbean nations. Puerto Rico and the US Virgin Islands use AST year-round without daylight saving time. The Canadian provinces switch to Atlantic Daylight Time (ADT) in summer.

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 AST and Beijing

With a +12h offset there is no overlap inside a normal 9 AM – 5 PM day. Beijing opens at 9:00 AM CST, which is 9:00 PM in AST, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

AST and Beijing have no shared working hours because of the +12h gap. Teams need to alternate early starts or rely on asynchronous handovers.

AST is 12 hours ahead of Beijing (AST UTC-04:00 → CST UTC+08:00). There is no shared 9-to-5 window, so plan around an early or late slot. Remember to re-check around daylight-saving transitions.

🕐 Daylight Saving Time Info

AST

☀ Currently in DST

Standard: UTC-04:00 · DST: UTC-03:00

Clocks fall back on Sun, Nov 1, 2026

Beijing

Does not observe DST

Frequently Asked Questions

What is the time difference between AST and Beijing?

AST (AST, UTC-04:00) is 12 hours ahead of Beijing (CST, UTC+08:00). The gap is currently +12h.

How do I convert AST time to Beijing time?

Add +12h to AST local time. For example, 9:00 AM in AST is 9:00 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 +12h offset from AST.

What is the best time to call Beijing from AST?

There is no shared working-hours window because of the +12h gap. The closest option is 1:00 PM in AST, which is 1:00 AM in Beijing.

Which is ahead, AST or Beijing?

AST is 12 hours ahead of Beijing. When it is 12:00 PM in AST it is 12:00 AM in Beijing.

Do AST and Beijing use different time zones?

AST uses AST at UTC-04:00, while Beijing (China) uses CST at UTC+08:00. The IANA identifiers are America/Halifax and Asia/Shanghai.

Does daylight saving time affect the AST–Beijing difference?

Neither zone observes daylight saving time, so the +12h offset between AST and Beijing is fixed all year.

Which other cities share AST's time zone?

AST also covers Halifax, San Juan, Santo Domingo, Caracas, La Paz, Fredericton, Charlottetown.

Which countries use AST, AST's zone?

AST is used in Canada (Atlantic provinces), Puerto Rico, US Virgin Islands, Dominican Republic, Venezuela, Bolivia, Barbados, Trinidad and Tobago.

Is there a day difference between AST and Beijing?

Sometimes. The +12h gap is large enough that 8:00 PM or later in AST already falls on the next day in Beijing.

What is the time difference between AST and Beijing?

Beijing is +12h from AST.

What timezone is AST in?

AST operates on its local timezone.

What timezone is Beijing in?

Beijing operates on its local timezone.

Which countries use AST (Atlantic Standard Time)?

AST is used in Canada (Atlantic provinces), Puerto Rico, US Virgin Islands, Dominican Republic, Venezuela, Bolivia, and 2 more countries.

Does AST observe daylight saving time?

Yes, AST switches to ADT during summer months.

What are some interesting facts about AST?

Puerto Rico uses AST year-round and does not observe DST. AST is 1 hour ahead of EST.

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 AST, what time is it in Beijing?

When it is 12:00 AM (midnight) in AST (AST), it is +12h later in Beijing (CST).