--:--:--
—
San Juan · Barbados · Halifax (winter)
For international scheduling, try the time meeting planner.
Difference
JST vs AST
UTC → UTC
--:--:--
—
Tokyo · Osaka · Yokohama
AST to JST converter
Convert AST to JST time now
Free AST to JST converter. See Atlantic Standard Time and Japan Standard Time side by side. Live clocks, a 13 hours gap, meeting hours, and a full-day chart for San Juan and Tokyo.
America/Puerto_Rico
—
AST → JST
To · Japan Standard Time
—
Asia/Tokyo
Interactive diagram
Watch AST convert into JST
Drag the Atlantic hour. Watch the Japan clock change.
Atlantic
9:00 AM AST
—
JST ← AST
Japan
—
Full-day chart
AST to JST hourly conversion chart
Full-day table. Tap a row to copy. Labels follow daylight saving.
| Atlantic | Japan | UTC offsets |
|---|
Meeting times
Best AST to JST meeting window
Find hours that work on both sides. Then save the slot to your calendar.
Follow along
Step-by-step AST to JST conversion
Four short steps to convert any AST time to JST.
Choose AST time
Select any hour in Atlantic Standard Time. Smart mode uses America/Puerto_Rico.
AST to JST conversion guide
AST to JST conversion guide
This AST to JST converter shows Japan Standard Time (UTC+9) for any Atlantic Standard Time (UTC−4) time. Use it to schedule between San Juan and Tokyo. Choose Smart DST for live city clocks. Choose Fixed mode when you only want the AST and JST labels.
Atlantic
AST
UTC−4
San Juan · Barbados · Halifax (winter)
AST vs JST—
Japan
JST
UTC+9
Tokyo · Osaka · Yokohama
What is AST to JST conversion?
AST to JST conversion turns a AST clock into the matching JST time. Use it for calls, travel, and teams in San Juan and Tokyo.
AST to JST time difference
JST is 13 hours ahead of AST. Add 13 hours to the AST time to get JST. The live clocks at the top show the current AST to JST gap.
AST vs JST
AST is UTC−4. JST is UTC+9. They are different names. If a region uses daylight saving, check the live labels.
AST to JST now / current time
Need ast to jst right now? Read the live clocks, or tap Use current time for an instant AST → JST result.
AST to JST time difference
Season / context — tap to explore
See how daylight saving can change this pair.
Atlantic—
—AST → JST
Japan—
Quick answers
Atlantic
Atlantic Standard Time (AST)
UTC−4
Atlantic Standard Time (AST) is UTC−4. Smart DST uses the city clock America/Puerto_Rico so daylight saving stays correct for San Juan · Barbados · Halifax (winter).
- Cities: San Juan · Barbados · Halifax (winter)
- City clock: America/Puerto_Rico
- Fixed AST: UTC−4
- On this page it pairs with JST (UTC+9)
Japan
Japan Standard Time (JST)
UTC+9
Japan Standard Time (JST) is UTC+9. Smart DST uses Asia/Tokyo for cities such as Tokyo · Osaka · Yokohama.
- Cities: Tokyo · Osaka · Yokohama
- City clock: Asia/Tokyo
- Fixed JST: UTC+9
- From AST: JST is 13 hours ahead of AST
AST to JST FAQ