Convert GMT to JST

Greenwich Mean Time (GMT) to Japan Standard Time (JST)

UK-Japan business relationships span finance (London-Tokyo stock exchanges), automotive (Toyota, Nissan UK operations), and tech partnerships. The 9-hour gap to GMT means very little overlap in standard business hours. In summer, UK clocks use BST, so London is 8 hours behind Tokyo, opening a slim but useful afternoon-morning window.

When it's 12:00 PM GMT, it's 9:00 PM in Tokyo

GMT UTC±0 JST UTC+9 +9h

Interactive Converter

Pick any time and date to convert between GMT and JST.

GMT to JST Conversion Table

Full 24-hour comparison. Business hours (9 AM -- 6 PM) are highlighted.

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

Best Meeting Window

Top meeting times for teams in GMT and JST (9 AM -- 6 PM work hours, 1-hour meeting).

12a

12p

GMT

Tokyo

Overlap

Everyone available

Most available

Some overlap

Outside work hours

1 4:00 AM -- 5:00 AM GMT

GMT: 4:00 AM Tokyo: 1:00 PM

1 of 2 members within working hours. 1 in mid-day range (9 AM–5 PM). Outside work hours for GMT.

5.9 / 10

2 5:00 AM -- 6:00 AM GMT

GMT: 5:00 AM Tokyo: 2:00 PM

1 of 2 members within working hours. 1 in mid-day range (9 AM–5 PM). Outside work hours for GMT.

5.9 / 10

3 12:00 PM -- 1:00 PM GMT

GMT: 12:00 PM Tokyo: 9:00 PM

1 of 2 members within working hours. 1 in mid-day range (9 AM–5 PM). Outside work hours for Tokyo.

5.9 / 10

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Scheduling Tips

Schedule meetings between 8:00-9:00 AM GMT / 5:00-6:00 PM JST to catch the UK morning and the final hour of the Japanese workday.
During BST, the overlap improves -- 8:00-10:00 AM BST / 4:00-6:00 PM JST gives you a full 2-hour window.
Avoid scheduling after 10:00 AM GMT as that pushes past 7:00 PM JST and into personal time in Japan.
For async handoffs, have the Tokyo team post updates before 6:00 PM JST so London sees them at 9:00 AM GMT the same day.

Time Difference & DST

JST is 9 hours ahead of GMT all year.

Dates	GMT	Tokyo	Difference
Jan 1, 2026 – Dec 31, 2027	UTC±0	UTC+9	+9h

GMT, Tokyo do not use daylight saving time.

UK clocks use BST (UTC+1) from the last Sunday in March to the last Sunday in October.

Use the interactive converter for a specific date.

Major Cities

Greenwich Mean Time (GMT)

Japan Standard Time (JST)

Tokyo
Osaka
Yokohama

Frequently Asked Questions

What is the time difference between GMT and JST?

JST (Japan Standard Time, UTC+9) is 9 hours ahead of GMT (UTC+0) all year. When it is 9:00 AM GMT, it is 6:00 PM in Tokyo. UK clocks use BST (UTC+1) from late March to late October, so London is 8 hours behind Tokyo in summer.

Does Japan observe daylight saving time?

No. Japan uses JST (UTC+9) year-round. The only seasonal change in the London-Tokyo offset comes from the UK side when it switches to BST, reducing the gap from 9 to 8 hours.

What time is 9 AM GMT in Tokyo?

9:00 AM GMT is 6:00 PM JST. During BST (summer), 9:00 AM BST is 5:00 PM JST. Either way, UK mornings catch the tail end of the Japanese business day.