Timezone abbreviation
HADT currently resolves here through America/Adak, where the live offset is -09:00 (HADT). This page expands that into the broader meaning set, top cities, countries, similar labels, and safer exact-zone equivalents.
Last updated Apr 26, 2026. Representative zones, offset ranges, and city usage are refreshed from the current timezone dataset so abbreviation pages stay tied to real zones instead of static boilerplate.
HADT is a North or South American civil-time label, currently 9h behind UTC at -09:00. The label covers 1 IANA zone across 1 country, with America/Adak as the busiest live reference.
This page uses America/Adak as the live reference at -09:00 (HADT). HADT works more as a reference label here than as a city-anchored civil-time label, so the IANA zone is what carries the practical weight.
HADT currently shows -09:00, but America/Adak observes seasonal clock changes — the next transition is around November 1, 2026. That means the offset on this page is a snapshot, not a permanent fact, so long-range scheduling should pin the underlying IANA zone instead of the abbreviation.
Live reference
America/Adak
Current offset
-09:00 (HADT)
Meanings / zones / countries
1 / 1 / 1
Offset range
UTC-10:00 to UTC-09:00
HADT is a US Pacific or Mountain band offset, so it is read more from western North America than from anywhere else. In practice it is read inside North America, where the leading city anchors are reference-only timezone clusters.
HADT is unusually unambiguous: it ties to a single country and a single IANA zone, which is closer to a national clock label than a multi-region abbreviation.
HADT shows up on broadcast guides, sports schedules, and inter-state corporate calendars. HADT can also flip to a sibling daylight-saving abbreviation later in the year, so timestamps before and after the change need to be read carefully.
United States sits in Americas, specifically North America. Population 340,110,988, area 9,525,067 km², capital Washington, D.C.. Civic markers behind HADT include English and USD (United States dollar, $).
United States backdrop: The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic consisting of 50 states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States also asserts sovereignty over five major island territories and various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's third-largest land area and third-largest population, exceeding 341 million.
HADT in the Hawaii-Aleutian Time meaning runs 9h behind UTC through North America, threading zones such as America/Adak (cities: reference cities). Country anchors: United States.
Hawaii-Aleutian Time
Current reading: HADT at -09:00 in United States.
America/Adak changes on November 1, 2026 at about 1:07 AM, moving from HAST (-10:00) to HAST (-10:00).
City anchors include reference cities, while country anchors include United States.
Live reference zone: America/Adak (HADT, -09:00)
Cities: reference-only mappings. Countries: United States.
Live zones: America/Adak (-09:00).
Countries
United States
Top cities
Reference-only meaning
United States runs on a single zone (0 mapped cities) under HADT. Visible cities: the lead reference city. Underlying zones: America/Adak.
City anchors for HADT (North America, currently -09:00). Pick a city to drop into a live local clock.
United States
Zones: America/Adak
Meaning group: Hawaii-Aleutian Time
HADT reads cleanly across the Americas in this dataset, but the same letters can mean different things elsewhere (notably CST, EST, and IST overlap with non-American labels). Pin the IANA zone when the audience is international.
America/Adak has an upcoming offset change on November 1, 2026. After that point, HADT on this page will read a different UTC offset until the next transition, so any saved timestamp should anchor to the IANA zone rather than the abbreviation.
For precise work, the safest equivalent of HADT is the exact IANA zone used by your city or system. America/Adak sits at -09:00, behind UTC, which means daily logs in this zone reach a new calendar date after UTC does — relevant for date-aligned reports and billing cutoffs.
Within this single zone (America/Adak, -09:00), HADT is unambiguous, so the abbreviation and the IANA zone effectively interchange.
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