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JST to KST Time Converter

Use this JST to KST time converter to compare Japan and South Korea time instantly. KST is 0 hours equal to JST, so 9:00 AM JST becomes 9:00 AM KST and 5:00 PM JST becomes 5:00 PM KST. The page is useful for business-hours overlap, international calls, remote-team handoffs, webinars, and travel planning, with daylight saving adjustments handled automatically.

JST Japan Standard Time
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KST Korea Standard Time
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Select a time to convert

JST to KST Quick Facts

Use this JST to KST converter to compare Japan and South Korea time, check the 0 hours gap, and confirm the right slot for calls, handoffs, and deadlines. Good overlap starts around 9:00 AM JST / 9:00 AM KST.

Time Difference
Japan Standard Time and Korea Standard Time are in the same time zone
Useful when deadlines, handoffs, or calls cross workday boundaries.
Best Call Window
Best overlap starts around 9:00 AM JST and 9:00 AM KST.
Common Use Cases
Useful for remote teams, customer support windows, travel planning, webinars, and same-day deadline handoffs.

How to Convert JST to KST

Converting between Japan Standard Time and Korea Standard Time means no offset adjustment — here's how to do it in under 10 seconds with no sign-up.

Enter Your JST Time

Pick the date and time in Japan Standard Time (UTC +9) that you want to convert. Hit "Now" to load the current JST time instantly, or use "+1h" to step forward and compare.

Read the KST Result

The equivalent Korea Standard Time (UTC +9) time appears immediately. Since KST is 0 hours behind of JST, most daytime conversions stay on the same calendar day.

Copy or Fine-Tune

Click "Copy Time" to grab the KST result for your calendar or message. Use "+1d" to check how the conversion shifts across dates — useful when Daylight Saving Time changes the gap.

Why Choose Our JST to KST Converter

Align JST–KST Meetings Instantly

When someone in Japan suggests 9:00 AM JST, that's 9:00 AM KST. This converter shows the overlap so both sides agree on one slot — no back-and-forth.

Spot Date-Line Shifts at a Glance

Late-night JST times can land on a different date in KST because of the 0 hours offset. The converter labels "next day" or "previous day" next to the result so you never send a message a day early or miss a deadline.

Handles DST Transitions Automatically

Daylight Saving adjustments can widen or narrow the JST–KST gap by an hour. During transition weeks many people get it wrong. This converter pulls the current UTC offsets automatically, so the result is right even on the changeover day.

Never Miss a JST-Timed Event

Product launches, sports matches, and webinars are often announced in JST. Convert the event time to KST so you know exactly when to tune in — since both zones share the same offset, no conversion is needed but this tool confirms it instantly.

JST to KST Time Conversion Chart

Quick-reference conversion table covering every hour of the day at a glance.

Complete 24-Hour Conversion

Japan Standard Time to Korea Standard Time full day schedule

12:00 AM
JST
12:00 AM
KST
1:00 AM
JST
1:00 AM
KST
2:00 AM
JST
2:00 AM
KST
3:00 AM
JST
3:00 AM
KST
4:00 AM
JST
4:00 AM
KST
5:00 AM
JST
5:00 AM
KST
6:00 AM
JST
6:00 AM
KST
7:00 AM
JST
7:00 AM
KST
8:00 AM
JST
8:00 AM
KST
9:00 AM
JST
9:00 AM
KST
10:00 AM
JST
10:00 AM
KST
11:00 AM
JST
11:00 AM
KST
12:00 PM
JST
12:00 PM
KST
1:00 PM
JST
1:00 PM
KST
2:00 PM
JST
2:00 PM
KST
3:00 PM
JST
3:00 PM
KST
4:00 PM
JST
4:00 PM
KST
5:00 PM
JST
5:00 PM
KST
6:00 PM
JST
6:00 PM
KST
7:00 PM
JST
7:00 PM
KST
8:00 PM
JST
8:00 PM
KST
9:00 PM
JST
9:00 PM
KST
10:00 PM
JST
10:00 PM
KST
11:00 PM
JST
11:00 PM
KST