JST to Z Converter
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Selected conversion
9:00 pm21:00 JST (UTC+9), Oct 18, 2026 = 12:00 pm12:00 Z (UTC+0), Oct 18, 2026
JST is 9 hours ahead of Z.
JST and Z examples
These examples always use JST (UTC+9) and Z (UTC+0). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.
JST is 9 hours ahead of Z.
How the time difference changes
JST is 9 hours ahead of Z year-round.
Working hours of 9:00 am to 6:00 pm in JST correspond to 12:00 am to 9:00 am in Z.Working hours of 09:00 to 18:00 in JST correspond to 00:00 to 09:00 in Z.
Compare JST time with Z time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Japan Standard Time is 9 hours ahead of Zulu Time Zone.
9:00 pm21:00 in JST is 12:00 pm12:00 in Z
JST to Z call time
Best time for a conference call or a meeting is between 5:30pm-6:30pm17:30-18:30 in JST which corresponds to 8:30am-9:30am08:30-09:30 in Z. Their 9am–6pm09:00–18:00 working hours do not overlap; this is a suggested compromise.
9:00 pm21:00 Japan Standard Time (JST). Offset UTC +9:00 hours
12:00 pm12:00 Zulu Time Zone (Z). Offset UTC 0:00 hours
9:00 pm21:00 JST / 12:00 pm12:00 Z
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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
Zulu Time Zone
Offset: Z is the same as Greenwich Mean Time (GMT).
Countries using this time zone: Antarctica, Burkina Faso, Faroe Islands, Gambia, Ghana, Greenland, Guernsey, Guinea, Guinea-Bissau, Iceland, Ireland, Isle of Man, Ivory Coast, Jersey, Liberia, Mali, Mauritania, Morocco, Portugal, Saint Helena, São Tomé and Príncipe, Senegal, Sierra Leone, Spain, Togo, United Kingdom, Western Sahara
Principal Cities: The largest city in the Z time zone is London in the United Kingdom, with about 8.962 million people. Other major cities in this time zone include Abidjan, Bamako, Casablanca, Dakar.
Coordinated Universal Time (UTC) is the world time standard that regulates clocks and time. It is the successor to Greenwich Mean Time (GMT). For casual use, UTC is the same as GMT, but UTC is the standard the scientific community uses.
UTC has been the time standard commonly used across the world since 1972. It is used in many technical fields, such as aviation and meteorology, and to synchronize time across internet networks.
Today some of the lighter areas are on UTC+1 (British Summer Time, Irish Standard Time, WEST).
Z representations, usage and related time zones
- Z - is the zone designator for the zero UTC/GMT offset, also known as 'Zulu' time
- +00 - basic short
- +0000 - basic
- +00:00 - extended
- +0000 - sign character (+) followed by a four digit time providing hours (00) and minutes (00) of the offset. Indicates the zero UTC/GMT offset.
- Zulu - Military abbreviation for Z
- Z - short form of 'Zulu'
- EGST - Eastern Greenland Summer Time
- GMT - Greenwich Mean Time
- WET - Western European Time
- AZOST - Azores Summer Time
- UTC - Coordinated Universal Time
- WT - Western Sahara Standard Time
- Z - Zulu Time Zone