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JST to GMT Time Converter

Use this JST to GMT time converter to compare Japan and United Kingdom time instantly. GMT is 9 hours behind JST, so 9:00 AM JST becomes 12:00 AM GMT and 5:00 PM JST becomes 8:00 AM GMT. 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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GMT Greenwich Mean Time
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Select a time to convert

JST to GMT Quick Facts

Use this JST to GMT converter to compare Japan and United Kingdom time, check the 9 hours gap, and confirm the right slot for calls, handoffs, and deadlines. Good overlap starts around 6:00 PM JST / 9:00 AM GMT.

Time Difference
Greenwich Mean Time is 9 hours behind Japan Standard Time
Useful when deadlines, handoffs, or calls cross workday boundaries.
Best Call Window
Best overlap starts around 6:00 PM JST and 9:00 AM GMT.
Common Use Cases
Useful for remote teams, customer support windows, travel planning, webinars, and same-day deadline handoffs.

How to Convert JST to GMT

Converting between Japan Standard Time and Greenwich Mean Time means accounting for a 9 hours gap — 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 GMT Result

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

Copy or Fine-Tune

Click "Copy Time" to grab the GMT result for your calendar or message. Use "+1d" to check how the conversion shifts across dates — helpful for scheduling recurring Japan–Universal calls.

Why Choose Our JST to GMT Converter

Align JST–GMT Meetings Instantly

When someone in Japan suggests 6:00 PM JST, that's 9:00 AM GMT. 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 GMT because of the 9 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–GMT 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 GMT so you know exactly when to tune in — with a 9 hours difference, a morning event in Japan hits the evening in Universal.

JST to GMT Time Conversion Chart

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

Complete 24-Hour Conversion

Japan Standard Time to Greenwich Mean Time full day schedule

12:00 AM
JST
3:00 PM
GMT
(previous day)
1:00 AM
JST
4:00 PM
GMT
(previous day)
2:00 AM
JST
5:00 PM
GMT
(previous day)
3:00 AM
JST
6:00 PM
GMT
(previous day)
4:00 AM
JST
7:00 PM
GMT
(previous day)
5:00 AM
JST
8:00 PM
GMT
(previous day)
6:00 AM
JST
9:00 PM
GMT
(previous day)
7:00 AM
JST
10:00 PM
GMT
(previous day)
8:00 AM
JST
11:00 PM
GMT
(previous day)
9:00 AM
JST
12:00 AM
GMT
10:00 AM
JST
1:00 AM
GMT
11:00 AM
JST
2:00 AM
GMT
12:00 PM
JST
3:00 AM
GMT
1:00 PM
JST
4:00 AM
GMT
2:00 PM
JST
5:00 AM
GMT
3:00 PM
JST
6:00 AM
GMT
4:00 PM
JST
7:00 AM
GMT
5:00 PM
JST
8:00 AM
GMT
6:00 PM
JST
9:00 AM
GMT
7:00 PM
JST
10:00 AM
GMT
8:00 PM
JST
11:00 AM
GMT
9:00 PM
JST
12:00 PM
GMT
10:00 PM
JST
1:00 PM
GMT
11:00 PM
JST
2:00 PM
GMT

JST to GMT Time Difference, Business Hours, and DST

JST to GMT is one of the more useful timezone conversions for calls, deadlines, and travel planning. The current gap is 9 hours, which means 9:00 AM JST becomes 12:00 AM GMT and 2:00 PM JST becomes 5:00 AM GMT.

This matters when teams in Tokyo and London need to align business hours, webinars, or customer-support coverage. Use the chart on this page when you want the exact conversion for today instead of relying on manual offset math.

Daylight saving changes can also shift the gap during the year, so a converter is safer than memorizing a fixed difference. That is especially important for recurring meetings and date-sensitive handoffs.