SGT to HST Converter
Understanding SGT and HST Time Zones
Singapore Time (SGT)
Singapore Time is observed in undefined and uses the offset UTC+8. Major cities in this time zone include Singapore, Kuala Lumpur. This time zone serves a significant global region with important economic and cultural hubs.
Hawaii Standard Time (HST)
Hawaii Standard Time operates at UTC-10, covering undefined. Key cities include Honolulu, Maui. The 18-hour backward offset from SGT means that when professionals in Singapore start their workday at 9:00 AM, it is already 3:00 PM in Honolulu.
SGT is also commonly referred to as Singapore time, Malaysia time, KL time. HST is also known as Hawaii Time, Honolulu time, Hawaiian time. So if you are searching for Singapore time to Hawaii Time, this is the same conversion as SGT to HST.
Complete SGT to HST Conversion Table
The table below shows every two-hour increment converted from Singapore Time to Hawaii Standard Time. Business hours (9 AM – 5 PM) are highlighted for easy scheduling reference.
| SGT (Singapore Time) | HST (Hawaii Standard Time) |
|---|---|
| 12:00 AM (00:00) | 6:00 AM (06:00) (previous day) |
| 2:00 AM (02:00) | 8:00 AM (08:00) (previous day) |
| 4:00 AM (04:00) | 10:00 AM (10:00) (previous day) |
| 6:00 AM (06:00) | 12:00 PM (12:00) (previous day) |
| 8:00 AM (08:00) | 2:00 PM (14:00) (previous day) |
| 10:00 AM (10:00) | 4:00 PM (16:00) (previous day) |
| 12:00 PM (12:00) | 6:00 PM (18:00) (previous day) |
| 2:00 PM (14:00) | 8:00 PM (20:00) (previous day) |
| 4:00 PM (16:00) | 10:00 PM (22:00) (previous day) |
| 6:00 PM (18:00) | 12:00 AM (00:00) |
| 8:00 PM (20:00) | 2:00 AM (02:00) |
| 10:00 PM (22:00) | 4:00 AM (04:00) |
Times shown in 12-hour and 24-hour format. Last updated 2026-03-09.
Scheduling Between SGT and HST
For business scheduling, the optimal overlap window between SGT and HST falls roughly between 9:00 AM and 11:00 AM SGT. This ensures both Singapore and Honolulu teams are within standard working hours.
The large 18-hour gap between SGT and HST means that finding overlapping working hours requires compromise from at least one side. Consider adopting asynchronous workflows — recorded video updates, shared documents, and time-zone-aware project management tools — to supplement the limited real-time overlap.
Travel Between Singapore and Honolulu
Travelers flying from Singapore to Honolulu should adjust their sleep schedule 18 days before departure at a rate of one hour per day. For this significant time difference, gradual adjustment reduces jet lag dramatically.
Medical experts recommend allowing approximately one day of adjustment per hour of time difference. For the 18-hour shift between SGT and HST, plan for roughly one week of gradual adjustment for optimal performance.
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 SGT to HST conversion specifically: SGT (UTC+8) and HST (UTC-10) neither observes DST, so the 18-hour offset remains constant throughout the year. This makes scheduling reliable and predictable.
Related Time Zone Conversions
References & Resources
Frequently Asked Questions
SGT (Singapore Time) is 18 hours ahead of HST (Hawaii Standard Time). SGT is UTC+8 and HST is UTC-10.
When it is 12:00 PM (noon) in SGT, it is 6:00 PM (previous day) in HST.
The best overlap for business hours is approximately 3:00 PM to 11:00 PM HST, which corresponds to 9:00 AM to 5:00 PM in SGT. Given the large gap, consider alternating between early and late meeting times.
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.