JST to GST Converter
Understanding JST and GST Time Zones
Japan Standard Time (JST)
Japan Standard Time is observed in undefined and uses the offset UTC+9. Major cities in this time zone include Tokyo, Osaka, Yokohama. This time zone serves a significant global region with important economic and cultural hubs.
Gulf Standard Time (GST)
Gulf Standard Time operates at UTC+4, covering undefined. Key cities include Dubai, Abu Dhabi, Doha. The 5-hour backward offset from JST means that when professionals in Tokyo start their workday at 9:00 AM, it is already 4:00 AM in Dubai.
JST is also commonly referred to as Japan time, Tokyo time, Japanese time. GST is also known as Dubai time, Gulf time, UAE time. So if you are searching for Japan time to Dubai time, this is the same conversion as JST to GST.
Complete JST to GST Conversion Table
The table below shows every two-hour increment converted from Japan Standard Time to Gulf Standard Time. Business hours (9 AM – 5 PM) are highlighted for easy scheduling reference.
| JST (Japan Standard Time) | GST (Gulf Standard Time) |
|---|---|
| 12:00 AM (00:00) | 7:00 PM (19:00) (previous day) |
| 2:00 AM (02:00) | 9:00 PM (21:00) (previous day) |
| 4:00 AM (04:00) | 11:00 PM (23:00) (previous day) |
| 6:00 AM (06:00) | 1:00 AM (01:00) |
| 8:00 AM (08:00) | 3:00 AM (03:00) |
| 10:00 AM (10:00) | 5:00 AM (05:00) |
| 12:00 PM (12:00) | 7:00 AM (07:00) |
| 2:00 PM (14:00) | 9:00 AM (09:00) |
| 4:00 PM (16:00) | 11:00 AM (11:00) |
| 6:00 PM (18:00) | 1:00 PM (13:00) |
| 8:00 PM (20:00) | 3:00 PM (15:00) |
| 10:00 PM (22:00) | 5:00 PM (17:00) |
Times shown in 12-hour and 24-hour format. Last updated 2026-03-09.
Scheduling Between JST and GST
For business scheduling, the optimal overlap window between JST and GST falls roughly between 2:00 PM and 5:00 PM JST. This ensures both Tokyo and Dubai teams are within standard working hours.
The moderate 5-hour gap between JST and GST means that there is a partial overlap of business hours. Teams can typically find a 3–4 hour window that works for both sides without requiring anyone to work outside normal hours.
Travel Between Tokyo and Dubai
Travelers flying from Tokyo to Dubai should adjust their sleep schedule 5 days before departure at a rate of one hour per day. For this time difference, gradual adjustment reduces jet lag dramatically.
Medical experts recommend allowing approximately one day of adjustment per hour of time difference. For the 5-hour shift between JST and GST, plan for about 5 days to fully acclimate.
Daylight Saving Time Considerations
During standard time months (November through March in the US), this offset is fixed. However, if either zone observes daylight saving time, the difference may temporarily shift by one hour during transition weeks in spring and autumn.
For the JST to GST conversion specifically: JST (UTC+9) and GST (UTC+4) neither observes DST, so the 5-hour offset remains constant throughout the year. This makes scheduling reliable and predictable.
Related Time Zone Conversions
References & Resources
Frequently Asked Questions
JST (Japan Standard Time) is 5 hours ahead of GST (Gulf Standard Time). JST is UTC+9 and GST is UTC+4.
When it is 12:00 PM (noon) in JST, it is 7:00 AM in GST.
The best overlap for business hours is approximately 4:00 AM to 12:00 PM GST, which corresponds to 9:00 AM to 5:00 PM in JST.
During standard time months (November through March in the US), this offset is fixed. However, if either zone observes daylight saving time, the difference may temporarily shift by one hour during transition weeks in spring and autumn.