The short answer

9pm in Atlantic Standard Time is 9am in Japan Standard Time on the next day.

Atlantic Standard Time is 12 hours behind Japan Standard Time. It falls outside the 9-to-5 in Atlantic Standard Time but lands inside working hours in Japan Standard Time.

Atlantic Standard Time
9pm
Japan Standard Time
9am
next day
Right now
3:39amADT · UTC-03:00 · Mon, Jun 22
3:39pmJST · UTC+09:00 · Mon, Jun 22
Read across to convert
Atlantic Standard Time
ADT · UTC-03:00
3:39am ☾
Japan Standard Time
JST · UTC+09:00
3:39pm ☀
Pinned9pmAtlantic Standard Time=9amJapan Standard Time · Tue (next day)
12amMon
12pm
WORK
1am
1pm
WORK
2am
2pm
WORK
NOW
3am
3pm
WORK
4am
4pm
WORK
5am
5pm
6am
6pm
7am
7pm
8am
8pm
9am
WORK
9pm
10am
WORK
10pm
11am
WORK
11pm
12pm
WORK
12amTue ·+1d
1pm
WORK
1amTue ·+1d
2pm
WORK
2amTue ·+1d
3pm
WORK
3amTue ·+1d
4pm
WORK
4amTue ·+1d
5pm
5amTue ·+1d
6pm
6amTue ·+1d
7pm
7amTue ·+1d
8pm
8amTue ·+1d
PINNED
9pm
9amTue ·+1d
WORK
10pm
10amTue ·+1d
WORK
11pm
11amTue ·+1d
WORK
daylightnightworking hoursoverlap
Best time to meet
No shared working hours.

Atlantic Standard Time and Japan Standard Time are too far apart for a working-day overlap. The least-unsociable option is an early-morning call on one side and an evening one on the other — or hand work off asynchronously and let the planet do the waiting.

Popular conversions

Quick reference.

9amAtlantic Standard Time=9pmJapan Standard Time
12pmAtlantic Standard Time=12amJapan Standard Time · next day
3pmAtlantic Standard Time=3amJapan Standard Time · next day
5pmAtlantic Standard Time=5amJapan Standard Time · next day
9pmAtlantic Standard Time=9amJapan Standard Time · next day
In context

What each side covers.

Atlantic Standard Time
ADT · UTC-03:00
3:39am

Canada & Caribbean

Japan Standard Time
JST · UTC+09:00
3:39pm
Cities on this clock

Frequently asked

Quick answers about converting between Atlantic Standard Time and Japan Standard Time. Can't find what you need? Email [email protected].

What is the time difference between Atlantic Standard Time and Japan Standard Time?
Atlantic Standard Time is 12 hours behind Japan Standard Time right now. We always show the live, daylight-saving-correct difference, so this figure already accounts for whichever side is observing summer time today.
When it's 9pm in Atlantic Standard Time, what time is it in Japan Standard Time?
9pm in Atlantic Standard Time is 9am in Japan Standard Time on the next day. It falls outside the 9-to-5 in Atlantic Standard Time but lands inside working hours in Japan Standard Time. Use the hour-by-hour table above to read any other time across.
What's the best time for a call between Atlantic Standard Time and Japan Standard Time?
There's no comfortable 9-to-5 overlap between Atlantic Standard Time and Japan Standard Time — they sit on opposite sides of the planet's working day. Plan for an early or late call on one side, or hand work off asynchronously.
Does this account for daylight saving time?
Yes. We track every clock change in both places, so the abbreviations you see — ADT and JST — are the ones actually in effect right now, not a fixed all-year value. When either side changes its clocks, this page updates automatically.
Why is the date sometimes different on each side?
When two places are far enough apart, the same moment can fall on different calendar days. That is why some conversions are marked "previous day" or "next day" — it is the same instant in time, read off two clocks that crossed midnight at different points.