World Timezones

AST-ATLANTIC to KST Converter

Compare KST to AST-ATLANTIC instead
Atlantic Time1:35 amFri, Jun 5
Atlantic TimeADT
North America · UTC-3
1:35 amFri, Jun 5
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a
12p
1p
2p
3p
4p
5p
6p
7p
8p
9p
10p
11p
Korea Standard TimeKST
Asia · UTC+9
1:35 pmFri, Jun 5
12p
1p
2p
3p
4p
5p
6p
7p
8p
9p
10p
11p
12a
1a
2a
3a
4a
5a
6a
7a
8a
9a
10a
11a

Offset

The time difference between Atlantic Time and Korea Standard Time is 12 hours.

12 hours

Atlantic Time (ADT) is behind Korea Standard Time (KST).

ADT: UTC-3

KST: UTC+9

Atlantic Time is currently observing daylight saving time; Korea Standard Time is not.

When to schedule

Standard business hours (9 AM–5 PM, Mon–Fri) in Atlantic Time and Korea Standard Time don't overlap on the same weekday. Korea Standard Time is 12 hours ahead of Atlantic Time.

With some flexibility, there are two workable windows outside standard hours, depending on which side takes the early or late slot:

  • 7 AM–8 AM in Atlantic Time (7 PM–8 PM in Korea Standard Time) — suggest 7:00 AM Atlantic Time (7:00 PM Korea Standard Time).
  • 7 PM–8 PM in Atlantic Time (7 AM–8 AM the next day in Korea Standard Time) — suggest 7:00 PM Atlantic Time (7:00 AM Korea Standard Time).

Either is an early start or late finish for one side, but workable for a one-off meeting.

This window may shift by an hour during daylight saving time.

Public holidays in 2026

National public holidays can affect availability — a counterpart is likely off work on their own holidays, so it's worth planning meetings and deadlines around them.

Canada

  • New Year's DayThu, Jan 1
  • Good FridayFri, Apr 3
  • Victoria DayMon, May 18
  • Canada DayWed, Jul 1
  • Labour DayMon, Sep 7
  • National Day for Truth and ReconciliationWed, Sep 30
  • ThanksgivingMon, Oct 12
  • Christmas DayFri, Dec 25

South Korea

  • New Year's DayThu, Jan 1
  • Lunar New YearMon, Feb 16
  • Lunar New YearTue, Feb 17
  • Lunar New YearWed, Feb 18
  • Independence Movement DayMon, Mar 2
  • Labour DayFri, May 1
  • Children's DayTue, May 5
  • Buddha's BirthdayMon, May 25
  • Local Election DayWed, Jun 3
  • Memorial DaySat, Jun 6
  • Constitution DayFri, Jul 17
  • Liberation DayMon, Aug 17
  • ChuseokThu, Sep 24
  • ChuseokFri, Sep 25
  • ChuseokSat, Sep 26
  • National Foundation DayMon, Oct 5
  • Hangul DayFri, Oct 9
  • Christmas DayFri, Dec 25

About these zones

Atlantic Time is also known as AST, or ADT. To call Canada, dial +1.

Korea Standard Time is also known as KST. To call South Korea, dial +82.

Korea Standard Time is approximately 6,700 miles north of Atlantic Time.

Quick reference

Full 24-hour conversion table — tap any time to open it in the converter.

AST-ATLANTICKSTDay
12:00 am12:00 pmSame day
1:00 am1:00 pmSame day
2:00 am2:00 pmSame day
3:00 am3:00 pmSame day
4:00 am4:00 pmSame day
5:00 am5:00 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
10:00 am10:00 pmSame day
11:00 am11:00 pmSame day
12:00 pm12:00 am+1 day
1:00 pm1:00 am+1 day
2:00 pm2:00 am+1 day
3:00 pm3:00 am+1 day
4:00 pm4:00 am+1 day
5:00 pm5:00 am+1 day
6:00 pm6:00 am+1 day
7:00 pm7:00 am+1 day
8:00 pm8:00 am+1 day
9:00 pm9:00 am+1 day
10:00 pm10:00 am+1 day
11:00 pm11:00 am+1 day

Daylight saving time

Atlantic Time observes daylight saving time; Korea Standard Time does not. The offset between the two zones changes when Atlantic Time transitions: on Sunday, November 1, 2026, clocks fall back from ADT to AST.

See the daylight saving time page for transition dates across every time zone.

Daylight today

Atlantic Time
Sunrise
5:31 AM
Sunset
8:56 PM
Day length
15h 25m
Korea Standard Time
Sunrise
5:12 AM
Sunset
7:51 PM
Day length
14h 38m

Daylight overlap: 2h 19m — 5:31 AM–7:51 AM in Atlantic Time (5:31 PM–7:51 PM in Korea Standard Time). Both locations are in daylight during this window.

Cities in these zones

Cities in Atlantic Time

Browse all cities to see the current local time anywhere.

Airports in these zones

Airports in Atlantic Time

  • YHZ

Airports in Korea Standard Time

  • GMP
  • ICN
  • PUS
  • TAE
  • CJJ
  • KWJ
  • MWX

Related conversions

Common conversions

What is 9:00 am AST-ATLANTIC in KST?
9:00 am AST-ATLANTIC is 9:00 pm KST.
What is 12:00 pm AST-ATLANTIC in KST?
12:00 pm AST-ATLANTIC is 12:00 am KST, the next day.
What is 12:30 pm AST-ATLANTIC in KST?
12:30 pm AST-ATLANTIC is 12:30 am KST, the next day.
What is 2:00 pm AST-ATLANTIC in KST?
2:00 pm AST-ATLANTIC is 2:00 am KST, the next day.
What is 5:00 pm AST-ATLANTIC in KST?
5:00 pm AST-ATLANTIC is 5:00 am KST, the next day.
What is 11:30 pm AST-ATLANTIC in KST?
11:30 pm AST-ATLANTIC is 11:30 am KST, the next day.