HST to GMT Converter
GMT is 10 hours ahead of HST
HST to GMT Conversion Table
Green rows indicate standard business hours (9 AM – 5 PM) in GMT
| HST | GMT |
|---|---|
| 12:00 AM | 10:00 AM |
| 1:00 AM | 11:00 AM |
| 2:00 AM | 12:00 PM |
| 3:00 AM | 1:00 PM |
| 4:00 AM | 2:00 PM |
| 5:00 AM | 3:00 PM |
| 6:00 AM | 4:00 PM |
| 7:00 AM | 5:00 PM |
| 8:00 AM | 6:00 PM |
| 9:00 AM | 7:00 PM |
| 10:00 AM | 8:00 PM |
| 11:00 AM | 9:00 PM |
| 12:00 PM | 10:00 PM |
| 1:00 PM | 11:00 PM |
| 2:00 PM | 12:00 AM +1d |
| 3:00 PM | 1:00 AM +1d |
| 4:00 PM | 2:00 AM +1d |
| 5:00 PM | 3:00 AM +1d |
| 6:00 PM | 4:00 AM +1d |
| 7:00 PM | 5:00 AM +1d |
| 8:00 PM | 6:00 AM +1d |
| 9:00 PM | 7:00 AM +1d |
| 10:00 PM | 8:00 AM +1d |
| 11:00 PM | 9:00 AM +1d |
Converting Hawaii Standard Time to Greenwich Mean Time
Hawaii Standard Time (HST) and Greenwich Mean Time (GMT) are separated by a 10 hours time difference. GMT is 10 hours ahead of HST. HST is UTC-10, used in United States, while GMT is UTC+0, used in United Kingdom, Ireland, Portugal.
When converting from HST to GMT, the key reference points to remember are: 9:00 AM HST equals 7:00 PM GMT, 12:00 PM noon HST equals 10:00 PM GMT, and 5:00 PM HST equals 3:00 AM GMT. The conversion table above shows every hour of the day mapped between these two time zones.
Scheduling Across HST and GMT
For professionals scheduling meetings between HST and GMT, finding overlapping business hours is essential. Standard business hours are typically 9:00 AM to 5:00 PM in each time zone. Given the 10 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
HST does not observe Daylight Saving Time, maintaining UTC-10 year-round. GMT observes DST, switching to BST (UTC+1). 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.