World Timezones

AST-ATLANTIC to JST Converter

Compare JST 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
Japan Standard TimeJST
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 Japan Standard Time is 12 hours.

12 hours

Atlantic Time (ADT) is behind Japan Standard Time (JST).

ADT: UTC-3

JST: UTC+9

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

When to schedule

Standard business hours (9 AM–5 PM, Mon–Fri) in Atlantic Time and Japan Standard Time don't overlap on the same weekday. Japan 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 Japan Standard Time) — suggest 7:00 AM Atlantic Time (7:00 PM Japan Standard Time).
  • 7 PM–8 PM in Atlantic Time (7 AM–8 AM the next day in Japan Standard Time) — suggest 7:00 PM Atlantic Time (7:00 AM Japan 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

Japan

  • New Year's DayThu, Jan 1
  • Coming of Age DayMon, Jan 12
  • Foundation DayWed, Feb 11
  • The Emperor's BirthdayMon, Feb 23
  • Vernal Equinox DayFri, Mar 20
  • Shōwa DayWed, Apr 29
  • Constitution Memorial DayWed, May 6
  • Greenery DayMon, May 4
  • Children's DayTue, May 5
  • Marine DayMon, Jul 20
  • Mountain DayTue, Aug 11
  • Respect for the Aged DayMon, Sep 21
  • Autumnal Equinox DayWed, Sep 23
  • Sports DayMon, Oct 12
  • Culture DayTue, Nov 3
  • Labour Thanksgiving DayMon, Nov 23

About these zones

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

Japan Standard Time is also known as JST. To call Japan, dial +81.

Japan 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-ATLANTICJSTDay
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; Japan 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
Japan Standard Time
Sunrise
4:27 AM
Sunset
6:55 PM
Day length
14h 28m

Daylight overlap: 1h 23m — 5:31 AM–6:55 AM in Atlantic Time (5:31 PM–6:55 PM in Japan 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 Japan Standard Time

  • HND
  • NRT
  • ITM
  • KIX
  • UKB
  • NGO
  • NKM
  • CTS
  • OKD
  • FUK

Related conversions

Common conversions

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