JST to GMT
Tokyo is 9 hours ahead of London in winter and 8 hours ahead while the UK is on British Summer Time, from the last Sunday of March to the last Sunday of October. 9:00 AM in Tokyo is midnight in London in January and 1:00 AM in June.
GMT, BST and a fixed UTC+9
JST is UTC+9 and never changes, so its difference to GMT, which equals UTC, is always exactly 9 hours. London's clocks are a different story: from the last Sunday of March the UK runs on BST (UTC+1), and the Tokyo–London gap drops to 8 hours until the last Sunday of October. If someone in Japan says a deadline is "17:00 GMT" in July, they may mean 17:00 UTC or 17:00 London time, which are an hour apart; ask which.
Japanese and British companies are closely linked. Nissan's plant in Sunderland is the largest car factory in the UK, Hitachi builds trains in County Durham, and London is a hub for Japanese banks and insurers in Europe. Those offices usually run a morning handover from Tokyo and an evening report back.
JST to GMT conversion table
Every hour of the day, using today's offsets (daylight saving is applied automatically).
| JST | GMT |
|---|---|
| 12:00 AM | 4:00 PM−1 |
| 1:00 AM | 5:00 PM−1 |
| 2:00 AM | 6:00 PM−1 |
| 3:00 AM | 7:00 PM−1 |
| 4:00 AM | 8:00 PM−1 |
| 5:00 AM | 9:00 PM−1 |
| 6:00 AM | 10:00 PM−1 |
| 7:00 AM | 11:00 PM−1 |
| 8:00 AM | 12:00 AM |
| 9:00 AM | 1:00 AM |
| 10:00 AM | 2:00 AM |
| 11:00 AM | 3:00 AM |
| JST | GMT |
|---|---|
| 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 |
Working hours that overlap (9:00–17:00 on both sides)
No weekday working hours overlap; one side has to stretch before 9:00 or after 17:00.
Daylight saving time
- Japan Standard TimeJST
No daylight saving; all year UTC+9
Japan
- Greenwich Mean TimeGMT / BST
UTC+0 in winter, UTC+1 in summer
United Kingdom, Ireland, Portugal
The afternoon-to-morning handover
London opens at 8:00 AM, which is 5:00 PM in Tokyo in winter and 4:00 PM in summer. That leaves a short daily window, roughly 4:00 to 6:00 PM in Tokyo, when both offices are at their desks: 7:00 to 9:00 AM in London in winter, 8:00 to 10:00 AM in summer. Currency desks treat this hour as the handoff from the Asian session to the European one.
For the evening direction, a 3:00 PM kickoff in London is midnight in Tokyo in winter and 11:00 PM in summer, which is why Premier League fans in Japan watch weekend matches late at night. To convert another city on the same date, open the time zone converter.
Other conversions with these zones
Frequently asked questions
- What time is it in Tokyo when London opens for business?
- 8:00 AM in London is 5:00 PM in Tokyo during GMT and 4:00 PM during British Summer Time.
- Is JST always UTC+9?
- Yes. Japan Standard Time has been UTC+9 with no seasonal change since 1951, so any change in the Tokyo–London gap comes from the UK clock.
- When does the Tokyo–London difference switch between 9 and 8 hours?
- It becomes 8 hours on the last Sunday of March, when the UK moves to BST, and returns to 9 hours on the last Sunday of October.
- What is 3 PM in London in Japan time?
- Midnight in Tokyo in winter, and 11:00 PM in summer while London is on BST.