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Sydney to AST

-14h

Sydney

AESTSOURCE
Australia · UTC+10:00DST observed
HH12
:
MM00
  
12:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM

AST

AST
UTC-03:00☀ DST active
HH10
:
MM00
  
(previous day)22:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM
Sydney
AST
12:00 AM
11:00 AM-1
2:00 AM
1:00 PM-1
4:00 AM
3:00 PM-1
6:00 AM
5:00 PM-1
8:00 AM
7:00 PM-1
10:00 AM
9:00 PM-1
12:00 PM
11:00 PM-1
2:00 PM
1:00 AM
4:00 PM
3:00 AM
6:00 PM
5:00 AM
8:00 PM
7:00 AM
10:00 PM
9:00 AM

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

AEST and AST on the World Map

The map below highlights the AEST (Australian Eastern Standard Time) and AST (Atlantic Standard Time) timezone regions across the globe.

AESTASTSydneyMelbourneBrisbaneCanberraHalifaxSan JuanSanto DomingoCaracas
AEST Zone
→
AST Zone

Explore all world timezones interactively →

AEST – Australian Eastern Standard Time

UTC+10:00

Australian Eastern Standard Time (AEST) covers eastern Australia, 10 hours ahead of UTC.

Countries in AEST
Australia (NSW, VIC, QLD, TAS, ACT)Papua New Guinea
Major Cities in AEST
SydneyMelbourneBrisbaneCanberraHobartGold Coast
Key Facts about AEST
  • •Queensland does not observe daylight saving time, staying on AEST year-round.
  • •Sydney and Melbourne switch to AEDT (UTC+11:00) in summer.
  • •The Australian Securities Exchange (ASX) operates on AEST/AEDT.
  • •AEST is 15 hours ahead of EST during winter.
Daylight Saving:Yes – switches to AEDT
Learn more about AEST on Wikipedia

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

About Sydney

Wikipedia

Sydney operates on Australian Eastern Standard Time (AEST/AEDT). As Australia's financial capital, Sydney opens global markets at the start of the business day.

Population:5.4 million
Metro:5.4 million
Business Hours:9:00 AM - 5:00 PM AEST
Currency:AUD (A$)
Stock Exchange:ASX (Australian Securities Exchange)
Key Landmarks
Sydney Opera HouseSydney Harbour BridgeBondi BeachDarling HarbourRoyal Botanic Garden
Did You Know?

Sydney is one of the first major cities to welcome the New Year.

Learn more about AEST timezone →

Sydney vs AST: Offsets, DST and Best Call Times

Sydney runs on Australian Eastern Standard Time (AEST) at UTC+10:00. AST runs on Atlantic Standard Time (AST) at UTC-04:00. That puts Sydney 14 hours behind AST — a difference of -14h at the current offsets.

In practice, when it is 9:00 AM in Sydney it is 7:00 PM in AST on the previous day. Midnight in Sydney is 10:00 AM in AST. Neither zone observes daylight saving time, so the offset between them stays constant all year.

Sydney to AST time conversion table

Sydney (AEST)AST (AST)Day
12:00 AM10:00 AMprevious day
6:00 AM4:00 PMprevious day
7:00 AM5:00 PMprevious day
8:00 AM6:00 PMprevious day
9:00 AM7:00 PMprevious day
12:00 PM10:00 PMprevious day
3:00 PM1:00 AMsame day
5:00 PM3:00 AMsame day
6:00 PM4:00 AMsame day
9:00 PM7:00 AMsame day

Why people convert Sydney to AST time

  • Scheduling a call from Sydney to AST: a 10:00 AM start in Sydney lands at 8:00 PM in AST the previous day, so you can confirm the slot without doing the arithmetic yourself.
  • Handling a -14h gap: Sydney and AST 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 AST is 7:00 PM in Sydney.
  • Watching a live event or market open: Sydney viewers need 7:00 PM in AST to catch a 9:00 AM start there, and 2:00 PM if the event is anchored to Sydney.
  • Always state the zone abbreviation, not just the hour. "3:00 PM AEST" is unambiguous; "3 PM" across a -14h gap is not.
  • With a -14h gap there is no shared 9-to-5 window, so alternate the early start: one week Sydney takes the early slot, the next week AST does.
  • Sydney: Clocks spring forward on Sat, Oct 3, 2026. Re-check this page after that date because the offset changes and so does the -14h gap.

About AEST (Australian Eastern Standard Time)

Australian Eastern Standard Time (AEST) is used in the eastern states of Australia including New South Wales, Victoria, Queensland, Tasmania, and the ACT. During summer (October to April), NSW, VIC, TAS, and ACT switch to Australian Eastern Daylight Time (AEDT, UTC+11:00), while Queensland remains on AEST year-round.

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.

Best time to call between Sydney and AST

With a -14h offset there is no overlap inside a normal 9 AM – 5 PM day. AST opens at 9:00 AM AST, which is 7:00 PM in Sydney, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

Sydney and AST have no shared working hours because of the -14h gap. Teams need to alternate early starts or rely on asynchronous handovers.

Sydney is 14 hours behind AST (AEST UTC+10:00 → AST UTC-04:00). 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

Sydney

❄ Currently in Standard Time

Standard: UTC+10:00 · DST: UTC+11:00

Clocks spring forward on Sat, Oct 3, 2026

AST

☀ Currently in DST

Standard: UTC-04:00 · DST: UTC-03:00

Clocks fall back on Sun, Nov 1, 2026

⚠ These locations are currently in different DST states, so the time difference may change when clocks adjust.

Frequently Asked Questions

What is the time difference between Sydney and AST?

Sydney (AEST, UTC+10:00) is 14 hours behind AST (AST, UTC-04:00). The gap is currently -14h.

How do I convert Sydney time to AST time?

Add -14h to Sydney local time. For example, 9:00 AM in Sydney is 7:00 PM in AST (previous day).

What time is it in AST right now?

AST uses AST at UTC-04:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -14h offset from Sydney.

What is the best time to call AST from Sydney?

There is no shared working-hours window because of the -14h gap. The closest option is 1:00 PM in Sydney, which is 11:00 PM in AST.

Which is behind, Sydney or AST?

Sydney is 14 hours behind AST. When it is 12:00 PM in Sydney it is 10:00 PM in AST.

Do Sydney and AST use different time zones?

Sydney (Australia) uses AEST at UTC+10:00, while AST uses AST at UTC-04:00. The IANA identifiers are Australia/Sydney and America/Halifax.

Does daylight saving time affect the Sydney–AST difference?

Neither zone observes daylight saving time, so the -14h offset between Sydney and AST is fixed all year.

Which other cities share Sydney's time zone?

AEST also covers Sydney, Melbourne, Brisbane, Canberra, Hobart, Gold Coast.

Which countries use AEST, Sydney's zone?

AEST is used in Australia (NSW, VIC, QLD, TAS, ACT), Papua New Guinea.

Is there a day difference between Sydney and AST?

Sometimes. The -14h gap is large enough that 8:00 PM or later in Sydney already falls on the in AST.

What is the time difference between Sydney and AST?

AST is -14h from Sydney.

What timezone is Sydney in?

Sydney operates on Australian Eastern Standard Time (AEST/AEDT). As Australia's financial capital, Sydney opens global markets at the start of the business day.

What timezone is AST in?

AST operates on its local timezone.

What are the business hours in Sydney?

Standard business hours in Sydney are 9:00 AM - 5:00 PM AEST.

Which countries use AEST (Australian Eastern Standard Time)?

AEST is used in Australia (NSW, VIC, QLD, TAS, ACT), Papua New Guinea.

Does AEST observe daylight saving time?

Yes, AEST switches to AEDT during summer months.

What are some interesting facts about AEST?

Queensland does not observe daylight saving time, staying on AEST year-round. Sydney and Melbourne switch to AEDT (UTC+11:00) in summer.

Which cities are in the AST timezone?

Major cities in the AST timezone include Halifax, San Juan, Santo Domingo, Caracas, La Paz, Fredericton, Charlottetown.

What is the UTC offset for AST?

Atlantic Standard Time (AST) is at UTC-04:00. During daylight saving time, it shifts to ADT.

What should I know about the AST timezone?

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

When is it midnight in Sydney, what time is it in AST?

When it is 12:00 AM (midnight) in Sydney (AEST), it is -14h later in AST (AST).