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MSK to AST

-7h

MSK

MSKSOURCE
UTC+03:00
HH12
:
MM00
  
12:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM

AST

AST
UTC-03:00☀ DST active
HH05
:
MM00
  
05:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM
MSK
AST
12:00 AM
6:00 PM-1
2:00 AM
8:00 PM-1
4:00 AM
10:00 PM-1
6:00 AM
12:00 AM
8:00 AM
2:00 AM
10:00 AM
4:00 AM
12:00 PM
6:00 AM
2:00 PM
8:00 AM
4:00 PM
10:00 AM
6:00 PM
12:00 PM
8:00 PM
2:00 PM
10:00 PM
4:00 PM

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

MSK and AST on the World Map

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

MSKASTMoscowSt. PetersburgVolgogradNizhny NovgorodHalifaxSan JuanSanto DomingoCaracas
MSK Zone
→
AST Zone

Explore all world timezones interactively →

MSK – Moscow Standard Time

UTC+03:00

Moscow Standard Time (MSK) is the time zone for Moscow and western Russia, 3 hours ahead of UTC.

Countries in MSK
Russia (Moscow, St. Petersburg, western regions)
Major Cities in MSK
MoscowSt. PetersburgVolgogradNizhny NovgorodKazanSamaraRostov-on-Don
Key Facts about MSK
  • •All Russian train timetables use Moscow Time, regardless of location.
  • •Russia abolished daylight saving time in 2011.
  • •Moscow is the most populous city in Europe with over 12 million residents.
  • •MSK shares the offset with Saudi Arabia (AST) and East Africa (EAT).
Daylight Saving:No – UTC+03:00 year-round
Learn more about MSK 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

Everything You Need to Know About MSK and AST Time

MSK runs on Moscow Standard Time (MSK) at UTC+03:00. AST runs on Atlantic Standard Time (AST) at UTC-04:00. That puts MSK 7 hours behind AST — a difference of -7h at the current offsets.

In practice, when it is 9:00 AM in MSK it is 2:00 AM in AST. Midnight in MSK is 5:00 PM in AST. Neither zone observes daylight saving time, so the offset between them stays constant all year.

MSK to AST time conversion table

MSK (MSK)AST (AST)Day
12:00 AM5:00 PMprevious day
6:00 AM11:00 PMprevious day
7:00 AM12:00 AMsame day
8:00 AM1:00 AMsame day
9:00 AM2:00 AMsame day
12:00 PM5:00 AMsame day
3:00 PM8:00 AMsame day
5:00 PM10:00 AMsame day
6:00 PM11:00 AMsame day
9:00 PM2:00 PMsame day

Why people convert MSK to AST time

  • Scheduling a call from MSK to AST: a 10:00 AM start in MSK lands at 3:00 AM in AST, so you can confirm the slot without doing the arithmetic yourself.
  • Finding shared working hours: both MSK and AST are inside the 9-to-5 working day between 4:00 PM and 5:00 PM MSK time (9:00 AM–10:00 AM AST). That is roughly 1 hours of usable overlap.
  • Booking travel or deliveries: tracking AST local time against MSK keeps pickup windows and arrival estimates honest across the -7h offset.
  • Always state the zone abbreviation, not just the hour. "3:00 PM MSK" is unambiguous; "3 PM" across a -7h gap is not.
  • Block 4:00 PM–5:00 PM MSK as the recurring meeting window if you work primarily from MSK and need AST colleagues present.

About MSK (Moscow Standard Time)

Moscow Standard Time (MSK) is the time zone used in Moscow, St. Petersburg, and much of western Russia. Russia abolished DST in 2011, so MSK is observed year-round. MSK is also the reference time for Russian railways – all train schedules in Russia are given in Moscow Time regardless of the actual local time zone.

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 MSK and AST

Both MSK and AST sit inside the 9 AM – 5 PM working day between 4:00 PM–5:00 PM MSK, which is 9:00 AM–10:00 AM AST. That gives roughly 1 hours of shared time — the safest window for a live call or meeting.

Business hours overlap

MSK and AST overlap for only 60 minutes (4:00 PM–5:00 PM MSK), so meetings have to be booked precisely.

MSK is 7 hours behind AST (MSK UTC+03:00 → AST UTC-04:00). The shared working window is 4:00 PM–5:00 PM MSK. Remember to re-check around daylight-saving transitions.

🕐 Daylight Saving Time Info

MSK

Does not observe DST

AST

☀ Currently in DST

Standard: UTC-04:00 · DST: UTC-03:00

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:

⏳
History of Timekeeping
From sundials to atomic clocks - 5000 years of measuring time
🌍
How Time Zones Work
UTC, offsets, and why zones don't follow straight lines
☀️
Daylight Saving Time
DST dates, which countries observe it, and the ongoing debate

Frequently Asked Questions

What is the time difference between MSK and AST?

MSK (MSK, UTC+03:00) is 7 hours behind AST (AST, UTC-04:00). The gap is currently -7h.

How do I convert MSK time to AST time?

Add -7h to MSK local time. For example, 9:00 AM in MSK is 2:00 AM in AST.

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 -7h offset from MSK.

What is the best time to call AST from MSK?

Call between 4:00 PM and 5:00 PM MSK — that maps to 9:00 AM–10:00 AM AST and keeps both parties inside the working day.

Which is behind, MSK or AST?

MSK is 7 hours behind AST. When it is 12:00 PM in MSK it is 5:00 AM in AST.

Does daylight saving time affect the MSK–AST difference?

Neither zone observes daylight saving time, so the -7h offset between MSK and AST is fixed all year.

Which other cities share MSK's time zone?

MSK also covers Moscow, St. Petersburg, Volgograd, Nizhny Novgorod, Kazan, Samara, Rostov-on-Don.

Which countries use MSK, MSK's zone?

MSK is used in Russia (Moscow, St. Petersburg, western regions).

Is there a day difference between MSK and AST?

Not normally. The -7h gap only pushes the date over the previous day.

What is the time difference between MSK and AST?

AST is -7h from MSK.

What timezone is MSK in?

MSK operates on its local timezone.

What timezone is AST in?

AST operates on its local timezone.

Which countries use MSK (Moscow Standard Time)?

MSK is used in Russia (Moscow, St. Petersburg, western regions).

Does MSK observe daylight saving time?

No, MSK does not observe daylight saving time and remains at UTC+03:00 year-round.

What are some interesting facts about MSK?

All Russian train timetables use Moscow Time, regardless of location. Russia abolished daylight saving time in 2011.

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 MSK, what time is it in AST?

When it is 12:00 AM (midnight) in MSK (MSK), it is -7h later in AST (AST).

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