HST — Hawaii Standard Time
See HST time details, where it’s used in the United States, and compare or convert UTC-10 with other time zones.
Meaning and Usage Areas
HST stands for Hawaii Standard Time and uses UTC-10. It is used in the United States, including Hawaii, and does not observe daylight saving time.
DST and HDT Relationship
HST stays on standard time year-round with no DST changes. If you’re looking for the daylight counterpart, HDT is the related abbreviation, but HST itself does not shift seasonally.
Convert and Schedule Times
Compare HST with other zones using the visual time grid and hour-by-hour tables. Export meetings with ICS download or add events to Google Calendar and Gmail automatically.
How to Convert HST to Other Time Zones
Open the HST converter page: Go to https://www.xconvert.com/time-converter/hst-time-zone to open the visual comparison grid with Hawaii Standard Time pre-loaded. This view is useful when you are planning a call with contacts in Honolulu, coordinating travel timing within Hawaii, or lining up remote work across teams that need to compare HST against other cities visually.
Add comparison cities: Click + Add City and search for the cities you want to compare against HST. Good choices depend on your use case: add major business hubs for client calls, airline connection points for trip planning, or your distributed team’s locations so you can compare Honolulu, East Honolulu, Pearl City, Hilo, or Kailua against the places you work with most often.
Select a time range on the grid: Click Select to enter selection mode, then drag across the colored 24-hour timeline on the HST row to highlight a meeting window in purple. You can drag the center to move the whole range or use the left and right handles to fine-tune the start and end, which is especially helpful when you need to find overlap between Hawaii business hours and another team’s workday.
Export and share the result: Once a time range is selected, use the export options to send it out as an ICS download, Google Calendar event, Gmail draft, Copy to clipboard, or Share link. This is practical for sending a confirmed meeting slot to clients, sharing a travel-ready schedule with coworkers, or making sure everyone sees the converted time in their own calendar automatically.
About Hawaii Standard Time (HST)
HST stands for Hawaii Standard Time. Its exact offset is UTC-10, which means local time in HST is 10 hours behind Coordinated Universal Time.
HST is used in the United States. On this page, the principal cities associated with HST are Honolulu, East Honolulu, Pearl City, Hilo, and Kailua, making it the key reference time zone for scheduling activity across Hawaii.
HST is a standard-time abbreviation, and its daylight saving counterpart is HDT. Other abbreviations that share the same UTC offset of UTC-10 are CKT, TAHT, and W, which can matter when comparing timestamps or interpreting time labels in international systems.
HST and Daylight Saving Time
HST is identified as a standard-time abbreviation, and its daylight saving counterpart is HDT. That means when a schedule, calendar entry, or system label refers specifically to HST, it is referring to the standard-time form rather than the daylight variant.
If you are trying to determine when HST switches or need the exact dates for the current year, the key relationship to know is that the abbreviation changes to HDT during daylight saving usage. For practical scheduling, use the converter’s date picker row at the top to choose the exact day you care about and compare the result visually across cities before sending invitations or confirming travel plans.
Frequently Asked Questions
What does HST stand for?
HST stands for Hawaii Standard Time. It is the standard time abbreviation used for Hawaii-related time references on schedules, calendars, and world clock tools.
Because the abbreviation appears frequently in travel itineraries, meeting invites, and system timestamps, it helps to know that HST refers specifically to the standard-time form and not a generic label for every seasonal variation.
What is the UTC offset for HST?
HST is UTC-10. In practical terms, that means Hawaii Standard Time is 10 hours behind UTC when you are comparing global schedules or converting timestamps.
This exact offset is useful when reviewing international logs, planning calls, or checking whether a calendar event has been placed correctly for Hawaii-based participants. If a tool or export file labels an event as HST, the expected reference is UTC-10.
Is HST the same as HDT?
No. HST and HDT are not the same abbreviation, even though they are related. HST is the standard-time abbreviation, while HDT is its daylight saving counterpart.
This distinction matters when reading meeting invites, software logs, or travel schedules because the abbreviation tells you which seasonal time reference is being used. If you are coordinating something important, always confirm whether the event label says HST or HDT before sharing it.
Which cities use HST?
The principal cities listed for HST are Honolulu, East Honolulu, Pearl City, Hilo, and Kailua. These cities make HST especially relevant for business coordination, local event planning, and travel schedules within Hawaii.
If you are arranging a meeting with someone in Honolulu or comparing work hours across multiple Hawaiian cities, using HST as the base row in the converter gives you a clear visual reference. It is also useful for internal scheduling when teams or service providers operate across more than one city in Hawaii.
Which country uses HST?
HST is used in the United States. For users planning business, support coverage, or travel related to Hawaii, that makes HST the relevant U.S. time reference to compare against other domestic and international time zones.
This is especially important when a calendar system defaults to another U.S. time zone and you need to verify that Hawaii-based participants are seeing the correct local time. Using the HST row in the converter helps avoid mistakes caused by assuming all U.S. locations share the same offset.
When does HST change?
HST is the standard-time abbreviation, and its counterpart is HDT. When a schedule changes from standard time to the daylight form, the abbreviation changes from HST to HDT.
For actual meeting coordination, the safest approach is to use the date picker in the converter and review the selected day directly on the grid. That helps you confirm the correct label and local-time alignment before exporting an event or sending a share link.
Are there other abbreviations with the same UTC offset as HST?
Yes. The same-offset abbreviations listed for UTC-10 are CKT, TAHT, and W. This is useful when you are reading international timetables, software timestamps, or aviation and logistics data where different regions may use different abbreviations for the same offset.
Even when the UTC offset matches, the geographic region and seasonal rules can differ, so the abbreviation still matters. If you see one of these labels in a system, compare it carefully with HST before assuming it refers to Hawaii.