Offset
The time difference between Japan Standard Time and Atlantic Time is 12 hours.
Japan Standard Time (JST) is ahead of Atlantic Time (ADT).
JST: UTC+9
ADT: UTC-3
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 Japan Standard Time and Atlantic Time don't overlap on the same weekday. Atlantic Time is 12 hours behind Japan Standard Time.
With some flexibility, there’s a workable window outside standard hours:
- 7 PM–8 PM in Japan Standard Time (7 AM–8 AM in Atlantic Time) — suggest 7:00 PM Japan Standard Time (7:00 AM Atlantic Time).
This means an early start or late finish for one side, but it’s a reasonable slot 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.
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
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
About these zones
Japan Standard Time is also known as JST. To call Japan, dial +81.
Atlantic Time is also known as AST, or ADT. To call Canada, dial +1.
Atlantic Time is approximately 6,700 miles north of Japan Standard Time.
Quick reference
Full 24-hour conversion table — tap any time to open it in the converter.
| JST | AST-ATLANTIC | Day |
|---|---|---|
| 12:00 am | 12:00 pm | -1 day |
| 1:00 am | 1:00 pm | -1 day |
| 2:00 am | 2:00 pm | -1 day |
| 3:00 am | 3:00 pm | -1 day |
| 4:00 am | 4:00 pm | -1 day |
| 5:00 am | 5:00 pm | -1 day |
| 6:00 am | 6:00 pm | -1 day |
| 7:00 am | 7:00 pm | -1 day |
| 8:00 am | 8:00 pm | -1 day |
| 9:00 am | 9:00 pm | -1 day |
| 10:00 am | 10:00 pm | -1 day |
| 11:00 am | 11:00 pm | -1 day |
| 12:00 pm | 12:00 am | Same day |
| 1:00 pm | 1:00 am | Same day |
| 2:00 pm | 2:00 am | Same day |
| 3:00 pm | 3:00 am | Same day |
| 4:00 pm | 4:00 am | Same day |
| 5:00 pm | 5:00 am | Same day |
| 6:00 pm | 6:00 am | Same day |
| 7:00 pm | 7:00 am | Same day |
| 8:00 pm | 8:00 am | Same day |
| 9:00 pm | 9:00 am | Same day |
| 10:00 pm | 10:00 am | Same day |
| 11:00 pm | 11:00 am | Same 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
- Sunrise
- 4:27 AM
- Sunset
- 6:55 PM
- Day length
- 14h 28m
- Sunrise
- 5:31 AM
- Sunset
- 8:56 PM
- Day length
- 15h 25m
Daylight overlap: 1h 23m — 5:31 PM–6:55 PM in Japan Standard Time (5:31 AM–6:55 AM in Atlantic Time). Both locations are in daylight during this window.
Cities in these zones
Cities in Japan Standard Time
Cities in Atlantic Time
Browse all cities to see the current local time anywhere.
Airports in these zones
Airports in Japan Standard Time
- HND
- NRT
- ITM
- KIX
- UKB
- NGO
- NKM
- CTS
- OKD
- FUK
Airports in Atlantic Time
- YHZ
Related conversions
Common conversions
- What is 9:00 am JST in AST-ATLANTIC?
- 9:00 am JST is 9:00 pm AST-ATLANTIC, the previous day.
- What is 12:00 pm JST in AST-ATLANTIC?
- 12:00 pm JST is 12:00 am AST-ATLANTIC.
- What is 12:30 pm JST in AST-ATLANTIC?
- 12:30 pm JST is 12:30 am AST-ATLANTIC.
- What is 2:00 pm JST in AST-ATLANTIC?
- 2:00 pm JST is 2:00 am AST-ATLANTIC.
- What is 5:00 pm JST in AST-ATLANTIC?
- 5:00 pm JST is 5:00 am AST-ATLANTIC.
- What is 11:30 pm JST in AST-ATLANTIC?
- 11:30 pm JST is 11:30 am AST-ATLANTIC.