HST — Hawaii-Aleutian Standard Time
HST is Hawaii-Aleutian Standard Time, 10 hours behind UTC. It is a fixed offset: unlike a time zone, it does not change with the season — the zones that use it switch to a different abbreviation instead.
Current time in HST
21:46
Saturday, 1 August 2026
HST = UTC-10 · 10 hours behind UTC
Shown for 2 Aug 2026 07:46 UTC. The clock goes live as soon as scripts load.
UTC offset
UTC-10
Type
Standard time
Seasonal counterpart
None
The zones using it do not change their clocks
Meanings
1
Unambiguous
Is HST in force right now?
A zone only carries this abbreviation for part of the year. This is which of them were on it at 2 Aug 2026 07:46 UTC; the list is re-derived against your own clock when scripts load.
On HST now
- Pacific/Honolulu — Honolulu
Using a different abbreviation
- Every zone listed here was on HST.
Convert HST to other time zones
City clocks reflect whatever their zone is doing; where a city observes daylight saving time, its difference from HST changes twice a year. Use the time zone converter for a specific date.
Time zones and cities that use HST
Hawaii-Aleutian Standard Time · UTC-10
Why HST is not an identifier
HST is shorthand, not a standard. There is no registry of time zone abbreviations, no authority that assigns them, and nothing preventing two regions from adopting the same three letters — which is what makes codes like IST and CST unusable without context.
For anything a machine will read — a calendar invitation, a database column, an API response — use the IANA identifier of the zone (Pacific/Honolulu, for example) or an explicit UTC offset alongside the date. The identifier survives a change in the law; HST and its 10 hours offset do not.
Abbreviations on the same clock
Frequently asked questions
What does HST stand for?
HST stands for Hawaii-Aleutian Standard Time. It is 10 hours behind UTC, written UTC-10.
What is HST in UTC?
HST is UTC-10. To convert an HST time to UTC, add 10 hours.
Which time zone should I use instead of HST?
Use an IANA identifier — Pacific/Honolulu for Hawaii-Aleutian Standard Time — or state the UTC offset with the date. Abbreviations are not identifiers: they are not unique, they are not registered anywhere, and half of them change with the season. Calendar software resolves this automatically when you pick a city rather than typing letters.