The World Clock Converter
Event Planner

KST to JST Time Converter

Compare KST and JST instantly. The clocks below stay in sync with the IANA time-zone database, so daylight-saving transitions are handled automatically for both Seoul and Tokyo.

Saturday, Jul 25
03:34
:19PM
Today
Saturday, Jul 25
03:34
:19PM
Today

24-Hour Comparison Timeline

Green = working hours · Yellow = early/late · Red = night

● Best window: 9 AM–5 PM (Seoul)
🇰🇷Seoul
9AM
10AM
11AM
12PM
1PM
2PM
3PM
4PM
5PM
6PM
7PM
8PM
9PM
10PM
11PM
12AM
1AM
2AM
3AM
4AM
5AM
6AM
7AM
8AM
🇯🇵Tokyo
9AM
10AM
11AM
12PM
1PM
2PM
3PM
4PM
5PM
6PM
7PM
8PM
9PM
10PM
11PM
12AM
1AM
2AM
3AM
4AM
5AM
6AM
7AM
8AM

24-hour reference table

KST (Seoul)JST (Tokyo)
12:00 AM12:00 AM
01:00 AM01:00 AM
02:00 AM02:00 AM
03:00 AM03:00 AM
04:00 AM04:00 AM
05:00 AM05:00 AM
06:00 AM06:00 AM
07:00 AM07:00 AM
08:00 AM08:00 AM
09:00 AM09:00 AM
10:00 AM10:00 AM
11:00 AM11:00 AM
12:00 PM12:00 PM
01:00 PM01:00 PM
02:00 PM02:00 PM
03:00 PM03:00 PM
04:00 PM04:00 PM
05:00 PM05:00 PM
06:00 PM06:00 PM
07:00 PM07:00 PM
08:00 PM08:00 PM
09:00 PM09:00 PM
10:00 PM10:00 PM
11:00 PM11:00 PM

Daylight saving time

Neither Seoul nor Tokyo observes daylight saving time — the offset between KST and JST is fixed year-round.

Working-hours overlap

9 AM–5 PM KST (9 AM–5 PM JST) — the shared 9-to-5 window for meetings.

Frequently asked questions

What is the time difference between KST and JST?+

JST (UTC+09:00) is currently 0 hours ahead of KST (UTC+09:00). This page recalculates the offset live from the IANA time-zone database, including any daylight-saving transitions.

Does KST or JST observe daylight saving time?+

Neither Seoul nor Tokyo observes daylight saving time, so the offset stays fixed all year. Times on this page always reflect the current local rules.

What are the best meeting hours between Seoul and Tokyo?+

Standard 9–5 working hours in Seoul and Tokyo overlap from 9 AM to 5 PM KST (9 AM–5 PM JST). Schedule calls inside this window to keep both sides in normal business hours.

How do I quickly convert KST to JST?+

Use the live clocks and 24-hour reference table above. Pick any hour on the KST row to see the matching JST time. The Event Planner also lets you pick a specific date and share it with attendees.

Related converters