HST to UTC Converter
Understanding HST and UTC Time Zones
Hawaii Standard Time (HST)
Hawaii Standard Time is observed in undefined and uses the offset UTC-10. Major cities in this time zone include Honolulu, Maui. This time zone serves a significant global region with important economic and cultural hubs.
Coordinated Universal Time (UTC)
Coordinated Universal Time operates at UTC+0, covering undefined. Key cities include Global. The 10-hour forward offset from HST means that when professionals in Honolulu start their workday at 9:00 AM, it is already 7:00 PM in Global.
HST is also commonly referred to as Hawaii Time, Honolulu time, Hawaiian time. UTC is also known as Universal Time, Zulu time, GMT+0. So if you are searching for Hawaii Time to Universal Time, this is the same conversion as HST to UTC.
Complete HST to UTC Conversion Table
The table below shows every two-hour increment converted from Hawaii Standard Time to Coordinated Universal Time. Business hours (9 AM – 5 PM) are highlighted for easy scheduling reference.
| HST (Hawaii Standard Time) | UTC (Coordinated Universal Time) |
|---|---|
| 12:00 AM (00:00) | 10:00 AM (10:00) |
| 2:00 AM (02:00) | 12:00 PM (12:00) |
| 4:00 AM (04:00) | 2:00 PM (14:00) |
| 6:00 AM (06:00) | 4:00 PM (16:00) |
| 8:00 AM (08:00) | 6:00 PM (18:00) |
| 10:00 AM (10:00) | 8:00 PM (20:00) |
| 12:00 PM (12:00) | 10:00 PM (22:00) |
| 2:00 PM (14:00) | 12:00 AM (00:00) (next day) |
| 4:00 PM (16:00) | 2:00 AM (02:00) (next day) |
| 6:00 PM (18:00) | 4:00 AM (04:00) (next day) |
| 8:00 PM (20:00) | 6:00 AM (06:00) (next day) |
| 10:00 PM (22:00) | 8:00 AM (08:00) (next day) |
Times shown in 12-hour and 24-hour format. Last updated 2026-03-09.
Scheduling Between HST and UTC
Freelancers and contractors working across HST and UTC should clearly state their invoicing time zone. A 10-hour difference means an "end of business day" deliverable could mean very different things to each party.
The large 10-hour gap between HST and UTC 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 Honolulu and Global
For layover planning between undefined and undefined destinations, connecting flights often involve intermediate time zones. Use our converter to verify each leg independently to avoid missed connections.
Medical experts recommend allowing approximately one day of adjustment per hour of time difference. For the 10-hour shift between HST and UTC, plan for roughly one week of gradual adjustment for optimal performance.
Daylight Saving Time Considerations
Some regions within a time zone do not observe DST. Arizona (MST) and Hawaii (HST) stay on standard time year-round, which can create unexpected offsets with neighboring states during summer months.
For the HST to UTC conversion specifically: HST (UTC-10) and UTC (UTC+0) neither observes DST, so the 10-hour offset remains constant throughout the year. This makes scheduling reliable and predictable.
Related Time Zone Conversions
References & Resources
Frequently Asked Questions
HST (Hawaii Standard Time) is 10 hours behind UTC (Coordinated Universal Time). HST is UTC-10 and UTC is UTC+0.
When it is 12:00 PM (noon) in HST, it is 10:00 PM in UTC.
The best overlap for business hours is approximately 7:00 PM to 3:00 AM UTC, which corresponds to 9:00 AM to 5:00 PM in HST. Given the large gap, consider alternating between early and late meeting times.
Some regions within a time zone do not observe DST. Arizona (MST) and Hawaii (HST) stay on standard time year-round, which can create unexpected offsets with neighboring states during summer months.