GMT to JST Converter
JST is 9 hours ahead of GMT
GMT to JST Conversion Table
Green rows indicate standard business hours (9 AM – 5 PM) in JST
| GMT | JST |
|---|---|
| 12:00 AM | 9:00 AM |
| 1:00 AM | 10:00 AM |
| 2:00 AM | 11:00 AM |
| 3:00 AM | 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 | 12:00 AM +1d |
| 4:00 PM | 1:00 AM +1d |
| 5:00 PM | 2:00 AM +1d |
| 6:00 PM | 3:00 AM +1d |
| 7:00 PM | 4:00 AM +1d |
| 8:00 PM | 5:00 AM +1d |
| 9:00 PM | 6:00 AM +1d |
| 10:00 PM | 7:00 AM +1d |
| 11:00 PM | 8:00 AM +1d |
Converting Greenwich Mean Time to Japan Standard Time
Greenwich Mean Time (GMT) and Japan Standard Time (JST) are separated by a 9 hours time difference. JST is 9 hours ahead of GMT. GMT is UTC+0, used in United Kingdom, Ireland, Portugal, while JST is UTC+9, used in Japan.
When converting from GMT to JST, the key reference points to remember are: 9:00 AM GMT equals 6:00 PM JST, 12:00 PM noon GMT equals 9:00 PM JST, and 5:00 PM GMT equals 2:00 AM JST. The conversion table above shows every hour of the day mapped between these two time zones.
Scheduling Across GMT and JST
For professionals scheduling meetings between GMT and JST, finding overlapping business hours is essential. Standard business hours are typically 9:00 AM to 5:00 PM in each time zone. Given the 9 hours difference, the window of overlap may be limited, making early morning or late evening calls necessary for one party. Use the highlighted working hours in the conversion table above to quickly identify suitable meeting times.
Daylight Saving Time Considerations
GMT observes Daylight Saving Time, switching to BST (UTC+1) during summer months. JST does not observe DST, staying at UTC+9 year-round. During DST transitions, the time difference between these zones may temporarily change by 1 hour. Always verify the current offset during spring and fall transition periods.