BST to JST Converter
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Selected conversion
12:00 pm12:00 GMT (UTC+0), Nov 1, 2026 = 9:00 pm21:00 JST (UTC+9), Nov 1, 2026
GMT is 9 hours behind JST.
BST and JST examples
These examples always use BST (UTC+1) and JST (UTC+9). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.
BST is 8 hours behind JST.
How the time difference changes
For most of the year, BST is 8 hours behind JST. From Oct 25, 2026 to Mar 28, 2027, and from Oct 31, 2027 to Mar 26, 2028, GMT is 9 hours behind JST.
For most of the year, working hours of 9:00 am to 6:00 pm in BST correspond to 5:00 pm to 2:00 am (next day) in JST. At other times of the year, working hours of 9:00 am to 6:00 pm in GMT correspond to 6:00 pm to 3:00 am (next day) in JST.For most of the year, working hours of 09:00 to 18:00 in BST correspond to 17:00 to 02:00 (next day) in JST. At other times of the year, working hours of 09:00 to 18:00 in GMT correspond to 18:00 to 03:00 (next day) in JST.
Compare BST time with JST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Greenwich Mean Time is 9 hours behind Japan Standard Time.
12:00 pm12:00 in GMT is 9:00 pm21:00 in JST
GMT to JST call time
Best time for a conference call or a meeting is between 8:30am-9:30am08:30-09:30 in GMT which corresponds to 5:30pm-6:30pm17:30-18:30 in JST. Their 9am–6pm09:00–18:00 working hours do not overlap; this is a suggested compromise.
12:00 pm12:00 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
9:00 pm21:00 Japan Standard Time (JST). Offset UTC +9:00 hours
12:00 pm12:00 GMT / 9:00 pm21:00 JST
Choose an hour to update the converter. Day labels such as “next day” or “+1” are relative to the selected date in the first column. Use Up and Down arrow keys, Home or End to move between hours, then Enter or Space to select.
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British Summer Time
Offset: BST is 1 hour ahead of Greenwich Mean Time (GMT).
Countries using this time zone: Guernsey, Isle of Man, Jersey, United Kingdom
Principal Cities: The largest city in the BST time zone is London in the United Kingdom, with about 8.962 million people. Other major cities in this time zone include Birmingham, Glasgow, Manchester, Sheffield.
Greenwich Mean Time (GMT) originally referred to the mean solar time at the Royal Observatory in Greenwich, London. It is now often used to refer to Coordinated Universal Time (UTC) when this is viewed as a time zone, and in casual use the two are the same. In the military, GMT is known as Zulu time. Greenwich Mean Time was the same as Universal Time (UT), a standard astronomical concept used in many technical fields, until the introduction of UTC in 1972.
Current time in the United Kingdom: UK time now
Today the shaded areas are on UTC+0 (GMT).
BST representations, usage and related time zones
- +01 - basic short
- +0100 - basic
- +01:00 - extended
- +0100 - sign character (+) followed by a four digit time providing hours (01) and minutes (00) of the offset. Indicates an offset of one hour to the east of the zero meridian.
- Alpha - Military abbreviation for BST
- A - short form of 'Alpha'
- Europe/Belfast
- Europe/Guernsey
- Europe/Isle_of_Man
- Europe/Jersey
- Europe/London
- GB
- GB-Eire
- British Summer Time - UTC +1
- Bangladesh Standard Time - UTC +6
- Bougainville Standard Time - UTC +11
- BST - British Summer Time
- CET - Central European Time
- IST - Irish Standard Time
- WEST - Western European Summer Time
- A - Alpha Time Zone
- CET - Central European Time
- MEZ - Mitteleuropäische Zeit
- WAT - West Africa Time
- WST - Western Sahara Summer Time
- BMT - Biel Mean Time
Japan Standard Time
Offset: JST is 9 hours ahead of Greenwich Mean Time (GMT).
Countries using this time zone: Japan
Principal Cities: The largest city in the JST time zone is Tokyo in Japan, with about 9.733 million people. Other major cities in this time zone include Yokohama, Osaka, Nagoya, Sapporo.
Daylight Saving: Clocks in Japan Standard Time (JST) do not change for daylight saving time, so JST stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter; see upcoming clock changes worldwide.
Current time in Japan: Japan time now
JST representations, usage and related time zones
- +09 - basic short
- +0900 - basic
- +09:00 - extended
- +0900 - sign character (+) followed by a four digit time providing hours (09) and minutes (00) of the offset. Indicates an offset of nine hours to the east of the zero meridian.
- India - Military abbreviation for JST
- I - short form of 'India'
- Asia/Tokyo
- Japan
- AWDT - Australian Western Daylight Time
- CHOST - Choibalsan Summer Time
- I - India Time Zone
- IRKST - Irkutsk Summer Time
- JST - Japan Standard Time
- KST - Korea Standard Time
- PWT - Palau Time
- TLT - East Timor Time
- ULAST - Ulaanbaatar Summer Time
- WIT - Eastern Indonesian Time
- YAKT - Yakutsk Time