Portsmouth Time to JST Converter
JST is 9 hours ahead of GMT. 9:00 AM GMT = 6:00 PM JST.
JST is 9 hours ahead of GMT at the moment. To convert Portsmouth Time to JST, add 9 hours to the Portsmouth Time time: 9:00 AM GMT = 6:00 PM JST.
Portsmouth Time (Portsmouth time) is used in Portsmouth, UK. JST (Japan Time) is used in Japan.
Portsmouth Time to JST time conversion table
Portsmouth Time to JST on 7 Nov 2026. Today's date. Highlighted rows are 9 AM–5 PM in both places.
| Portsmouth Time | JST | Day |
|---|---|---|
| 12:00 AM GMT | 9:00 AM JST | — |
| 1:00 AM GMT | 10:00 AM JST | — |
| 2:00 AM GMT | 11:00 AM JST | — |
| 3:00 AM GMT | 12:00 PM JST | — |
| 4:00 AM GMT | 1:00 PM JST | — |
| 5:00 AM GMT | 2:00 PM JST | — |
| 6:00 AM GMT | 3:00 PM JST | — |
| 7:00 AM GMT | 4:00 PM JST | — |
| 8:00 AM GMT | 5:00 PM JST | — |
| 9:00 AM GMT | 6:00 PM JST | — |
| 10:00 AM GMT | 7:00 PM JST | — |
| 11:00 AM GMT | 8:00 PM JST | — |
| 12:00 PM GMT | 9:00 PM JST | — |
| 1:00 PM GMT | 10:00 PM JST | night |
| 2:00 PM GMT | 11:00 PM JST | night |
| 3:00 PM GMT | 12:00 AM JST | next day |
| 4:00 PM GMT | 1:00 AM JST | next day |
| 5:00 PM GMT | 2:00 AM JST | next day |
| 6:00 PM GMT | 3:00 AM JST | next day |
| 7:00 PM GMT | 4:00 AM JST | next day |
| 8:00 PM GMT | 5:00 AM JST | next day |
| 9:00 PM GMT | 6:00 AM JST | next day |
| 10:00 PM GMT | 7:00 AM JST | next day |
| 11:00 PM GMT | 8:00 AM JST | next day |
- Work rows — 9 AM–5 PM in both places
- Night in the destination (10 PM–6 AM)
How to convert Portsmouth Time to JST
Add 9 hours to the Portsmouth Time time to get JST.
Example: 9:00 AM GMT = 6:00 PM JST.
Across midnight: 10:00 PM GMT = 7:00 AM JST (next day). The date changes, so always check the day as well as the hour.
Time difference between Portsmouth Time and JST
The time difference between Portsmouth Time and JST is not the same all year, because the two sides change for daylight saving time on different dates. In 2026 it works out like this:
- 1 Jan 2026 – 28 Mar 2026: JST is 9 hours ahead of Portsmouth Time.
- 29 Mar 2026 – 24 Oct 2026: JST is 8 hours ahead of Portsmouth Time.
- 25 Oct 2026 – 31 Dec 2026: JST is 9 hours ahead of Portsmouth Time.
Portsmouth Time and JST during daylight saving time
- Portsmouth Time next changes on 28 Mar 2027: clocks go forward one hour at 00:59 local time, from GMT (UTC+0) to BST (UTC+1).
- JST does not observe daylight saving time; it stays on UTC+9 all year.
Best time for a meeting between Portsmouth Time and JST
Portsmouth Time and JST have no shared 9 AM–5 PM window. The earliest slot that is reasonable on both sides is 7:00 AM GMT, which is 4:00 PM JST.
Portsmouth Time to JST FAQ
What is the time difference between Portsmouth Time and JST?
Right now JST is 9 hours ahead of GMT. The gap changes 3 times in 2026 because the two sides switch to daylight saving time on different dates.
What is 9 AM Portsmouth Time in JST?
9:00 AM GMT is 6:00 PM JST.
What is 12 PM (noon) Portsmouth Time in JST?
12:00 PM GMT is 9:00 PM JST.
Is JST ahead of or behind Portsmouth Time?
JST is 9 hours ahead of GMT, so it is later in JST than in Portsmouth Time.
Does Portsmouth Time change for daylight saving time?
Yes. Portsmouth Time next changes on 28 Mar 2027, when clocks go forward one hour from GMT to BST.
Does JST change for daylight saving time?
No. JST stays on the same offset all year, so conversions never shift for daylight saving time.
What is the best time for a meeting between Portsmouth Time and JST?
Portsmouth Time and JST have no shared 9 AM–5 PM window. The earliest slot that is reasonable on both sides is 7:00 AM GMT, which is 4:00 PM JST.
Related conversions
Convert JST to Portsmouth Time
Convert Portsmouth Time to other time zones
Convert other time zones to JST
Learn more
Updated 7 November 2026. Time zone data: IANA tz database.