GMTtoJSTGreenwich Mean Time to Japan Standard Time
GMT
Greenwich Mean Time (GMT)JST
Japan Standard Time (GMT+9)Feasible Shoulder Hours Window
Recommended calling window between GMT and JST
There are no overlapping 9-to-5 working hours between GMT and JST. The optimal compromise window falls during morning/evening shoulder periods (7:00 AM – 9:00 PM) when participants in both locations are awake.
24-Hour Schedule Conversion Matrix
Compare every hour of the day between GMT and JST.
| GMT Time (Greenwich Mean Time) | JST Time (Japan Standard Time) | Status & Recommendation |
|---|---|---|
| 00:00AM | 09:00AM | ⚪ Outside Work Hours |
| 01:00AM | 10:00AM | ⚪ Outside Work Hours |
| 02:00AM | 11:00AM | ⚪ Outside Work Hours |
| 03:00AM | 12:00PM | ⚪ Outside Work Hours |
| 04:00AM | 13:00PM | ⚪ Outside Work Hours |
| 05:00AM | 14:00PM | ⚪ Outside Work Hours |
| 06:00AM | 15:00PM | ⚪ Outside Work Hours |
| 07:00AM | 16:00PM | ⚪ Outside Work Hours |
| 08:00AM | 17:00PM | ⚪ Outside Work Hours |
| 09:00AM | 18:00PM | 🟡 Feasible (Shoulder Hour) |
| 10:00AM | 19:00PM | 🟡 Feasible (Shoulder Hour) |
| 11:00AM | 20:00PM | 🟡 Feasible (Shoulder Hour) |
| 12:00PM | 21:00PM | ⚪ Outside Work Hours |
| 13:00PM | 22:00PM | ⚪ Outside Work Hours |
| 14:00PM | 23:00PM | ⚪ Outside Work Hours |
| 15:00PM | 00:00AM | ⚪ Outside Work Hours |
| 16:00PM | 01:00AM | ⚪ Outside Work Hours |
| 17:00PM | 02:00AM | ⚪ Outside Work Hours |
| 18:00PM | 03:00AM | ⚪ Outside Work Hours |
| 19:00PM | 04:00AM | ⚪ Outside Work Hours |
| 20:00PM | 05:00AM | ⚪ Outside Work Hours |
| 21:00PM | 06:00AM | ⚪ Outside Work Hours |
| 22:00PM | 07:00AM | ⚪ Outside Work Hours |
| 23:00PM | 08:00AM | ⚪ Outside Work Hours |
Frequently Asked Questions
What is the time difference between GMT and JST?
JST is 9 hours ahead of GMT. When it is 12:00 PM (noon) in GMT, the current synchronized time in JST is 9:00 PM.
What are the overlapping working hours between GMT and JST?
Due to the timezone separation, standard 9-to-5 working shifts do not overlap. The recommended compromise window falls during morning/evening shoulder periods (7:00 AM – 12:00 PM in GMT = 4:00 PM – 9:00 PM in JST).
Does daylight saving time affect the conversion between GMT and JST?
Yes. GMT observes daylight saving shifts, moving the offset by 1 hour on scheduled transition dates.
What regions and major cities observe GMT and JST?
GMT (Greenwich Mean Time) is primarily observed across Western Europe & West Africa (United Kingdom, Ireland, Portugal, Ghana) (key hubs include London, Dublin, Lisbon, Accra). JST (Japan Standard Time) is observed across East Asia (Japan) (key hubs include Tokyo, Osaka, Yokohama, Nagoya).
What is 9:00 AM GMT in JST?
9:00 AM in GMT corresponds to 6:00 PM in JST. You can cross-reference every hour of the day in the 24-hour visual schedule table above.
Which time zone is ahead, GMT or JST?
JST is ahead by 9 hours.