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List of UTC offsets
List of UTC offsets
List of UTC offsets
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This is a list of the UTC time offsets, showing the difference in hours and minutes from Coordinated Universal Time (UTC), from the westernmost (−12:00) to the easternmost (+14:00). It includes countries and regions that observe them during standard time or year-round.

The main purpose of this page is to list the current standard time offsets of different countries, territories and regions. Information on daylight saving time or historical changes in offsets can be found in the individual offset articles (e.g. UTC+01:00) or the country-specific time articles (e.g. Time in Russia).

Places that observe daylight saving time (DST) during their respective summer periods are listed only once, at the offset for their winter (usually known as "standard") period; see their individual articles for more information. A source for detailed DST and historical information is the tz database. Note that there are many instances of unofficial observation of a different offset (and/or DST) than expected by areas close to borders, usually for economic reasons.[1]

In the section names, the letter after the offset is that used in nautical time, with which the UTC offset section overlaps at least partially. Nautical time strictly partitions the globe at 15 degrees, whereas UTC offsets can deviate, for instance according to borders. If present, a dagger (†) indicates the usage of a nautical time zone letter outside of the standard geographic definition of that time zone.

Some zones that are north/south of each other in the mid-Pacific differ by 24 hours in time – they have the same time of day but dates that are one day apart. The two extreme time zones on Earth (both in the mid-Pacific) differ by 26 hours.

Standard Time Zones, as of January 2, 2024

In the following list, only the rightmost indent of a group of locations is meant to indicate the area observing the offset; the places above and to the left are meant solely to indicate the area's parent administrative divisions. For example, the entry of Eucla explains that Eucla observes the specified time offset, and the state (Western Australia) and country (Australia) are shown only for reference and are not meant to be wholly included as observing that offset.

The purpose of the "principal cities" list at the top of some of the time zone entries is to give a brief list of major cities. These should be limited to a maximum of one city per country (within each zone), and not all countries in a zone need to have a city listed. Similarly, time zones need not have any cities listed if there are no major cities in that offset.

UTC−12:00, Y

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UTC−11:00, X

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UTC−10:00, W

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Principal cities: Honolulu

UTC−09:30, V†

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UTC−09:00, V

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Principal cities: Anchorage

UTC−08:00, U

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Principal cities: Los Angeles, Vancouver, Tijuana

UTC−07:00, T

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Principal cities: Denver, Calgary, Ciudad Juárez

UTC−06:00, S

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Principal cities: Mexico City, Chicago, Guatemala City, Tegucigalpa, Winnipeg, San José, San Salvador

UTC−05:00, R

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Principal cities: New York, Toronto, Havana, Lima, Bogotá, Kingston, Quito

UTC−04:00, Q

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Principal cities: Santiago, San Juan, Santo Domingo, Manaus, Caracas, La Paz, Halifax

UTC−03:30, P†

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Principal cities: St. John's

UTC−03:00, P

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Principal cities: São Paulo, Buenos Aires, Montevideo

UTC−02:00, O

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UTC−01:00, N

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UTC+00:00, Z

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Principal cities: London, Dublin, Lisbon, Abidjan, Accra, Dakar

UTC+01:00, A

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Principal cities: Berlin, Frankfurt, Rome, Stockholm, Paris, Madrid, Warsaw, Lagos, Kinshasa, Algiers, Casablanca

UTC+02:00, B

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Principal cities: Athens, Bucharest, Cairo, Helsinki, Jerusalem, Johannesburg, Khartoum, Kyiv, Riga, Sofia

UTC+03:00, C

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Principal cities: Moscow, Istanbul, Riyadh, Baghdad, Addis Ababa, Doha, Nairobi, Kuwait City

UTC+03:30, C†

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Principal cities: Tehran

UTC+04:00, D

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Principal cities: Dubai, Baku, Tbilisi, Yerevan, Samara

UTC+04:30, D†

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Principal cities: Kabul

UTC+05:00, E

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Principal cities: Karachi, Astana, Tashkent, Yekaterinburg

UTC+05:30, E†

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Principal cities: Delhi, Mumbai, Colombo

UTC+05:45, E*

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Principal cities: Kathmandu

UTC+06:00, F

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Principal cities: Dhaka, Omsk, Bishkek

UTC+06:30, F†

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Principal cities: Yangon

UTC+07:00, G

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Principal cities: Jakarta, Ho Chi Minh City, Bangkok, Krasnoyarsk

UTC+08:00, H

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Principal cities: Shanghai, Taipei, Hong Kong, Kuala Lumpur, Singapore, Perth, Manila, Makassar, Irkutsk

UTC+08:45, H*

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UTC+09:00, I

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Principal cities: Tokyo, Seoul, Pyongyang, Jayapura, Chita

UTC+09:30, I†

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Principal cities: Adelaide

UTC+10:00, K

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Principal cities: Sydney, Melbourne, Brisbane, Port Moresby, Vladivostok

UTC+10:30, K†

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UTC+11:00, L

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Principal cities: Nouméa

UTC+12:00, M

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Principal cities: Auckland, Suva, Petropavlovsk-Kamchatsky

UTC+12:45, M*

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UTC+13:00, M†

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UTC+14:00, M††

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See also

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References

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Revisions and contributorsEdit on WikipediaRead on Wikipedia

List of UTC offsets

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from Grokipedia
A list of UTC offsets is a compilation of the standardized time differences, measured in hours and minutes, between (UTC)—the global time standard—and the local times observed in various countries, regions, territories, and islands worldwide. These offsets define time zones and facilitate international coordination for travel, communications, and commerce. Offsets typically range from UTC−12:00, observed on uninhabited Baker Island in the Pacific Ocean, to UTC+14:00, used in the inhabited Line Islands of Kiribati, spanning a total of 26 hours across the globe. While the majority of offsets are whole-hour increments aligned with Earth's 24-hour rotation and longitude divisions of 15 degrees, exceptions include half-hour variations like UTC+5:30 in India and Sri Lanka, and UTC+9:30 in the Northern Territory and South Australia. Quarter-hour offsets, such as UTC+12:45 on the Chatham Islands of New Zealand during daylight saving time, are even rarer. As of 2025, approximately 38 distinct UTC offsets are in active use globally, though this number can fluctuate due to political decisions, such as changes in national time policies or the adoption of daylight saving time (DST) in certain regions, which temporarily shifts offsets by one hour. Comprehensive lists of UTC offsets are maintained in authoritative databases like the IANA Time Zone Database (tz database), which tracks historical, current, and future offsets for over 500 unique time zones to ensure accurate software and system implementations. This resource underscores the dynamic nature of timekeeping, influenced by geography, governance, and historical conventions.

Background

Definition and Concepts

Coordinated Universal Time (UTC) serves as the world's primary time standard, providing a reference for civil timekeeping and synchronizing clocks across international borders. It is realized through an ensemble of highly accurate atomic clocks operated by national metrology institutes and coordinated by the International Bureau of Weights and Measures (BIPM). is derived from (TAI), a continuous scale defined by the steady accumulation of atomic seconds since , 1958, but incorporates adjustments to remain closely aligned with Earth's irregular rotation and solar day length. When was officially introduced on , , it was initialized as TAI minus 10 seconds to match the prevailing astronomical time scale, with subsequent leap seconds inserted as needed—totaling 27 to date—resulting in TAI currently leading by 37 seconds. A UTC offset denotes the fixed or standard difference in hours and minutes between the local mean time at a given and UTC, conventionally formatted as UTC±HH:MM, where positive values indicate time ahead of UTC and negative values indicate time behind. This offset enables the conversion between local times and the universal reference, supporting global activities such as , , and financial transactions that require precise temporal coordination. Offsets are typically whole hours but can include fractions like 30 or 45 minutes in certain regions to better accommodate local or historical conventions. Time zones represent contiguous geographical areas adopting the same , ideally delineated by 15-degree meridians of to reflect the Earth's 24-hour rotation cycle, thereby ensuring that local noon roughly aligns with solar noon. However, boundaries are frequently adjusted to conform to political, economic, or cultural divisions, such as national borders or regional administrative lines, prioritizing administrative efficiency over strict longitudinal adherence. This flexible structuring allows over 40 distinct time zones worldwide, promoting uniformity within communities while accommodating diverse international needs. While standard UTC offsets provide year-round consistency, many regions implement (DST), a that advances local clocks by one hour—typically from spring to fall—to extend evening daylight, thereby shifting the effective offset (e.g., North America's Eastern of UTC−05:00 becomes Eastern Daylight Time of UTC−04:00 during DST observance). Not all areas observe DST, and its application varies by , adding a layer of variability to local-UTC relations. Collectively, UTC offsets span from UTC−12:00 in remote Pacific locales to UTC+14:00 in portions of , encompassing every inhabited territory and facilitating seamless global time management.

Notation Systems

UTC offsets are commonly expressed in the standard notation UTC±HH:MM, where HH represents hours and MM represents minutes, with a positive sign (+) indicating time zones east of the and a negative sign (−) for those west of it. This format precisely denotes the difference from (UTC), such as UTC+01:00 for one hour ahead or UTC−08:00 for eight hours behind. The notation adheres to international conventions for clarity in global communications, ensuring unambiguous representation of time differences. The (ISO) 8601 standard formalizes this notation within date-time strings, using Z to designate (zero offset) and the ±HH:MM format for others, as in 2025-11-08T14:30:00−05:00. This compliance facilitates machine-readable timestamps across systems, with the offset appended directly to the time component without spaces. supports fractional offsets beyond whole hours, such as ±HH:30 for half-hour variations, promoting interoperability in data exchange. In military and NATO contexts, single-letter phonetic codes provide brevity, particularly in aviation and defense operations. These alphabetic designations, derived from the , map to UTC offsets: for instance, Y for UTC−12:00, Z for (Zulu time), and A for UTC+01:00. Letters progress alphabetically eastward from Z, skipping J to avoid confusion with numbers, and are often appended to times like "0600Z" for 06:00 UTC. This system, standardized for operational efficiency, remains in use despite its limitations for non-hourly offsets. Regional abbreviations offer localized shorthand for common offsets, such as PST for Pacific Standard Time (UTC−08:00) in or CET for (UTC+01:00) in Europe. These acronyms simplify everyday references but vary with (DST), shifting to PDT (UTC−07:00) or CEST (UTC+02:00) during observation periods. While convenient, they lack the universality of UTC notation and can lead to ambiguity across regions sharing similar names. Non-hourly UTC offsets, which deviate from whole-hour increments, follow the same ±HH:MM structure to reflect their rarity and specificity, such as UTC+05:30 for Standard Time or UTC−03:30 for Newfoundland Standard Time. These notations highlight the diversity in global timekeeping, accommodating historical and geographical nuances without additional symbols in standard formats.

Historical Development

Early Timekeeping and Time Zones

Before the mid-19th century, timekeeping relied on local , where clocks were set based on the apparent position of the sun reaching its highest point, or noon, at each specific location. This system worked adequately for agrarian societies but became problematic with the expansion of railroads and telegraph networks, as traveling across regions encountered hundreds of differing local times, leading to scheduling chaos and safety risks. For instance, alone, over 100 local times were in use by the 1880s, complicating coordination for the growing rail industry. To address these inconsistencies, American and Canadian railroads collaboratively introduced the first standardized time zones on November 18, 1883, dividing North America into four main zones—Eastern, Central, Mountain, and Pacific—each offset from Greenwich Mean Time (GMT) by whole hours, with the Eastern zone at five hours behind GMT (equivalent to modern UTC−05:00). This initiative, proposed by railroad superintendent Charles Dowd and refined by the General Time Convention, marked the practical beginning of offset-based timekeeping, though adoption was initially voluntary and limited to rail operations. The following year, the International Meridian Conference in Washington, D.C., formalized GMT as the global reference meridian, recommending the division of Earth into 24 time zones, each ideally spanning 15 degrees of longitude for one-hour offsets. Attended by representatives from 25 nations, the conference established a universal day starting at midnight GMT but stopped short of mandating strict zone boundaries, leaving implementation to individual countries. Despite these advancements, early time zone adoption faced significant challenges due to political and geographical considerations, resulting in irregular boundaries and experimental offsets. For example, while most initial zones used whole-hour differences from GMT, some regions opted for half-hour variations to better align with local or administrative needs; British India introduced its standard time in as 5 hours and 30 minutes ahead of GMT (UTC+05:30), rejecting a proposed two-zone system to maintain national uniformity across its vast longitude span. Such deviations arose from the tension between ideal 15-degree zones and practical borders, with governments prioritizing sovereignty over precision. By the , most countries had aligned to hourly offsets from GMT, facilitating global communication and trade, though political anomalies like half-hour zones persisted in places such as and Newfoundland. GMT later evolved into (UTC) as the modern standard.

Establishment of UTC

Coordinated Universal Time (UTC) originated in the 1960s as a response to the need for a precise, atomic-based time standard that could replace the astronomical Greenwich Mean Time (GMT) while maintaining synchronization with Earth's irregular rotation. The International Radio Consultative Committee (CCIR), a predecessor to the ITU Radiocommunication Sector, formalized the UTC system through its Study Group 7 in Geneva in 1962, aiming to integrate the stability of atomic clocks with the practical requirements of universal timekeeping. This effort was driven by advancements in atomic frequency standards, which provided greater accuracy than solar-based observations, and UTC was initially conceived to disseminate coordinated time signals globally starting from 1 January 1960. The system was officially adopted with the inclusion of leap seconds in 1972, marking the transition to a hybrid timescale that balanced atomic precision and astronomical alignment, following the CCIR's Recommendation 374 of 1963 and further refinements at the 1970 plenary assembly. At its core, UTC is defined as (TAI) minus the cumulative number of leap seconds, resulting in a difference of 37 seconds as of 2025, with leap seconds periodically inserted or (theoretically) subtracted to ensure UTC remains within 0.9 seconds of UT1, the solar-based timescale tied to . TAI itself is a continuous scale maintained by over 400 atomic clocks worldwide, coordinated by the International Bureau of Weights and Measures (BIPM), providing uninterrupted seconds of exactly 9,192,631,770 periods of the cesium-133 atom's resonance frequency. Leap seconds are added at the end of or December when slows sufficiently, as determined by observations, to prevent cumulative drift in civil timekeeping; no negative leap seconds have been required to date. This structure allows UTC to serve as a stable reference for both scientific and everyday applications, superseding GMT's purely astronomical basis. The UTC system was implemented on 1 January 1972, ensuring that radio signals and navigation systems aligned with the new atomic-adjusted scale. The shift eliminated ambiguities in international time coordination, as GMT had been inconsistently interpreted between astronomical and solar definitions, and facilitated uniform global standards for and . The (ITU) further endorsed UTC through its World Administrative Radio Conference for Space in in 1971, recommending its use in space applications, and the 1979 World Administrative Radio Conference, which mandated UTC as the standard for timekeeping worldwide. Following its formalization, UTC saw widespread global adoption by the , with most nations updating their time zone offsets to align explicitly with UTC, including adjustments in remote regions like Pacific islands that previously referenced GMT equivalents. For instance, several Pacific territories recalibrated their offsets during this period to better integrate with and communication networks standardized on UTC. Ongoing geopolitical changes continue to prompt adjustments, such as Samoa's 2011 switch from UTC+13:00 to UTC−11:00 on 29 December, which involved skipping an entire day to reposition the country west of the for economic alignment with and . Today, the International Earth Rotation and Reference Systems Service (IERS) maintains UTC by monitoring via and astronomical data, announcing leap seconds six months in advance through Bulletin C; the most recent addition was on 31 December 2016, with no further insertions as of 2025 due to observed rotational acceleration. In November 2022, the General Conference on Weights and Measures (CGPM) adopted Resolution 4, resolving to discontinue the practice of leap seconds no later than 2035 to promote uniformity in timekeeping systems.

List of UTC Offsets West of and at UTC

UTC−12:00

UTC−12:00 is the standard time offset that is twelve hours behind (UTC), representing the westernmost fixed offset in global timekeeping. This zone is observed exclusively by and , two small, uninhabited coral atolls in the central administered by the as unincorporated territories within its minor outlying islands. Located approximately 1,900 miles southwest of , these islands span about 2.1 square kilometers combined and lie at coordinates near 0° N and 176° W . With no permanent human population, they function primarily as national wildlife refuges for seabirds and marine life, supporting occasional scientific expeditions focused on ecology, , and , as well as serving as key waypoints for trans-Pacific and routes. The UTC−12:00 offset on these islands is fixed year-round, with no observance of , ensuring consistent timing for any transient activities such as operations or satellite calibration. In military and designations, this zone is labeled "Y" for time, facilitating coordinated operations across international datelines in , maritime, and defense contexts where precise synchronization is critical. The islands' position immediately west of the positions UTC−12:00 as the last to transition into a new day, creating a 24-hour lag from UTC and underscoring its role in global deadline management for software releases, financial settlements, and international agreements. Historically, the assignment of UTC−12:00 to and Howland Islands dates back to at least 1949, reflecting their alignment with the and early nautical conventions for Pacific territories, though formal standardization occurred as part of broader U.S. policies in the late to support uninhabited outposts. As of November 2025, the offset continues unchanged, with the islands remaining devoid of infrastructure beyond basic markers for conservation and navigation, and no adjustments reported in U.S. territorial administration. This stability preserves UTC−12:00 as a niche but essential reference in an era of increasingly digitized global timing systems.

UTC−11:00

UTC−11:00 is a time offset from (UTC), subtracting 11 hours, and serves as the for several Pacific island territories and locations. This offset is primarily observed in , including its capital Pago Pago, the independent territory of , and the uninhabited U.S. minor outlying island of . These areas lie in the central , positioned adjacent to the , which influences their temporal isolation from other global regions. The UTC−11:00 zone operates as standard time year-round without any observance of daylight saving time (DST), maintaining a fixed 11-hour lag behind UTC. This consistency avoids seasonal clock adjustments, aligning with the equatorial proximity and minimal daylight variation in these low-latitude locations. Unlike nearby offsets such as UTC−10:00 used in , UTC−11:00 positions these territories on the western side of the Date Line, resulting in dates that are typically one day behind much of the Pacific. In military and NATO contexts, UTC−11:00 is designated as X-ray time (X). American Samoa, as a U.S. unincorporated territory, has a population of approximately 46,000 residents, concentrated mainly on the island of Tutuila, where the offset facilitates coordination with U.S. federal operations, including economic ties to tuna processing and remittances. Niue, with its smaller population of around 1,600, similarly uses this offset for administrative and international synchronization. As of 2025, no changes to the UTC−11:00 offset have been implemented in these locations, and has consistently rejected proposals to introduce DST, as seen in decisions during the to maintain alignment with U.S. non-DST territories rather than adopting temporary adjustments. This stability supports local governance and economic activities without the disruptions of time shifts.

UTC−10:00

UTC−10:00 is a time offset that is ten hours behind (UTC), primarily observed in the central region. This offset is used in the state of , , where it is known as Hawaii Standard Time (HST), covering all islands in the Hawaiian archipelago. It is also employed in the and other parts of , designated as Tahiti Time (TAHT), including major locations such as on . Additionally, the observe this offset as Cook Islands Time (CKT) throughout the year. In military contexts, particularly under standards, UTC−10:00 is referred to as "Whiskey" time (W). Hawaii has maintained a fixed UTC−10:00 offset without observing daylight saving time (DST) since September 1945, when wartime DST ended and the state opted out of future implementations due to its equatorial proximity, where daylight variations are minimal. This decision was formalized in 1967 by the , exempting the state from federal DST provisions under the . The offset was selected to align closely with local , as Hawaii's (approximately 155°W) falls within the natural boundaries for a ten-hour lag from UTC, promoting consistency in daily activities despite the islands' remote position. This serves a resident population of approximately 1.4 million people, concentrated mainly on Oahu. In French Polynesia, UTC−10:00 applies year-round to the (including , , and ) and the Tuamotu Archipelago, without DST, reflecting the region's stable tropical climate. The similarly use a fixed UTC−10:00, having discontinued DST in 2023 after previous seasonal advancements to UTC−09:00 from 2011 to 2022, to simplify timekeeping and align with trading partners like . As of 2025, the offset remains stable across these jurisdictions, with facing occasional legislative proposals to resume DST but no enacted changes, preserving the fixed schedule for economic and cultural reasons.

UTC−09:30

UTC−09:30 is the time offset used exclusively in the Marquesas Islands, an archipelago in French Polynesia, where it is designated as Marquesas Time (MART). This zone applies to the inhabited islands of the group, including Nuku Hiva, Hiva Oa, Ua Pou, and Tahuata, serving the region's remote communities. The offset positions local time 9 hours and 30 minutes behind Coordinated Universal Time (UTC), providing a distinct temporal framework within the broader Pacific time system. The operates as a fixed standard without adjustments, ensuring year-round consistency for daily activities, navigation, and coordination with mainland . This stable offset was selected to approximate local solar noon more closely than neighboring hourly zones, reflecting the islands' geographical position approximately 1,400 kilometers northeast of . Historically, the zone transitioned from (approximately UTC−09:18) to the current UTC−09:30 in October 1912, establishing MART as a permanent standard to support uniform timekeeping across the . As of 2025, the maintain this offset without alteration, accommodating a of roughly 9,000 residents who rely on it for local , , and cultural practices. UTC−09:30 stands out as one of the rare half-hour deviations in the and Pacific regions, highlighting the nuanced adaptations in global time standardization to accommodate isolated locales.

UTC−09:00

UTC−09:00 is a time offset nine hours behind (UTC), primarily used in the and the of . In the United States, this offset corresponds to Alaska Standard Time (AKST) and covers the majority of , including major cities such as Anchorage, Fairbanks, and Juneau, serving a population of approximately 741,000 residents. The offset was formally adopted for most of in 1983, when the state consolidated its four previous time zones into two, with over 98% of the population aligning to this zone to simplify coordination and commerce. In the military and contexts, UTC−09:00 is designated as "V" or Victor time. In French Polynesia, UTC−09:00 applies year-round to the Gambier Islands (known as Gambier Time or GAMT), a remote archipelago in the eastern Tuamotu group with a small population centered around Rikitea. This fixed offset contrasts with other parts of French Polynesia, such as the Marquesas Islands at UTC−09:30 and the Society Islands at UTC−10:00. Alaska observes daylight saving time (DST), advancing clocks to UTC−08:00 (Alaska Daylight Time, AKDT) during the summer period. As of 2025, DST in Alaska begins at 2:00 a.m. on the second Sunday in March (March 9) and ends at 2:00 a.m. on the first Sunday in November (November 2). Notably, the neighboring Yukon Territory in Canada, which previously observed Pacific Time with DST aligning temporarily to UTC−07:00, eliminated seasonal clock changes in 2020 to remain on UTC−07:00 (Yukon Time) year-round.

UTC−08:00

is the time offset used as standard time in the , encompassing major regions of western and the . This offset applies year-round in the and serves as (PST) in parts of the (including all of , Washington, most of and , and northern ), most of in , and the state of in . In and contexts, UTC−08:00 is designated as Uniform Time (U). During (DST), which is observed from the second Sunday in March to the first Sunday in November, regions in the advance clocks by one hour to UTC−07:00, becoming Pacific Daylight Time (PDT); this practice continues as of 2025 in the , , and . The , however, have maintained UTC−08:00 as a fixed standard since 1998, without DST. The was standardized on November 18, 1883, when North American railroads adopted uniform time zones to replace local solar times, facilitating coordinated rail operations across the . This offset covers an estimated of approximately 50 million people, primarily concentrated in and . In , rejoined the DST observance in 2023, aligning with neighboring U.S. states after most of the country discontinued the practice.

UTC−07:00

UTC−07:00 is the standard time offset used in the Mountain Time Zone across parts of , particularly during the non-daylight saving period. This offset corresponds to Mountain Standard Time (MST) and is observed in several U.S. states including , , (southern portion), (western portion), , (western portion), , (southwestern portion), (eastern portion), (western portion), (western portion), , and . In , it applies to most of , the eastern portions of , the western part of , and certain communities in such as Kugaaruk and . In , the state of Chihuahua, including border municipalities like , utilizes this offset to align with adjacent U.S. regions. The offset is designated as "T" or Time in and contexts, facilitating coordinated operations across international boundaries by standardizing time references relative to (UTC). During (DST), most areas in the Mountain Time Zone advance to UTC−06:00, known as Mountain Daylight Time (MDT), typically from the second in to the first in ; however, (excluding the [Navajo Nation](/page/Navajo Nation)) has maintained permanent MST since 1968 to conserve energy in its hot , avoiding the additional evening heat that could increase demands. The [Navajo Nation](/page/Navajo Nation) within does observe DST to synchronize with surrounding states. Chihuahua's time zone alignment was adjusted in 2023 for border areas to follow U.S. DST patterns, though as a whole discontinued nationwide DST in 2022, with exceptions for economic . As of 2025, approximately 25 million people reside in regions observing as , encompassing diverse geographies from the to arid deserts and northern territories, supporting industries like energy, , and . This population figure includes about 20 million in the U.S. portions and additional residents in Canadian and Mexican areas, reflecting steady growth in urban centers such as , Phoenix, and . The fixed use in underscores regional adaptations to local climate and energy needs, while DST observance in other parts promotes uniformity with broader North American schedules.

UTC−06:00

UTC−06:00 is the time offset from Coordinated Universal Time (UTC) used as standard time in the Central Time Zone across parts of North America. This zone primarily encompasses the central regions of the United States and Canada, including major areas such as Texas, Illinois, and Manitoba, as well as central Mexico around Mexico City. It also applies year-round in the Galápagos Islands of Ecuador and as standard time on Easter Island in Chile. The is the most populous in the United States, home to approximately 95 million residents, representing about 29% of the national population, with significant urban centers like and contributing to its density. In , it covers provinces such as (central parts) and , while in , it includes most of the country's central and eastern states, where it has been fixed without (DST) changes since 2022. The zone's extensive use reflects the longitudinal span from roughly 97.5° W to 82.5° W. In the Galápagos Islands, , known as Galápagos Time (GALT), operates year-round without DST, a policy maintained since Ecuador abolished DST nationwide after the 1992–1993 season. Easter Island similarly uses as Easter Island Standard Time (EAST) during non-DST periods, though it observes DST by advancing to from September to April; the island's standard offset was reaffirmed in Chile's 2019 DST adjustments without a permanent shift. These Pacific locations highlight the offset's application beyond continental , occasionally extending to select South Pacific islands for alignment with regional commerce. In military contexts, particularly under standards, is designated as "S" or Sierra Time, facilitating coordinated operations in regions like the . For civilian use in the and , (CST or Central Standard Time) shifts to during DST as Central Daylight Time (CDT), typically from March to November, affecting transportation, broadcasting, and daily schedules across the zone's vast area.

UTC−05:00

UTC−05:00 is a time offset from (UTC) that is primarily observed as the standard time in the across parts of . This offset serves major urban centers such as and in the United States, as well as and in , encompassing states like , Georgia, and New York, and provinces including and . In and the , it is the fixed year-round time for countries including (e.g., ), (e.g., ), mainland (e.g., ), and (e.g., Kingston). In and contexts, UTC−05:00 is designated as "" time (R), part of the phonetic alphabet system for coordinating operations across time zones, where it represents a five-hour lag behind UTC. For use in , it corresponds to Eastern Standard Time (EST), which advances to Eastern Daylight Time (EDT, UTC−04:00) during (DST) periods, typically from the second Sunday in March to the first Sunday in November. This offset supports daily activities for a substantial portion of the continent's , estimated at approximately 145 million people in the United States and combined, highlighting its economic and cultural significance in regions like the U.S. Northeast and Midwest urban corridors. In contrast to North American practices, remains fixed without DST in most adopting South American nations to maintain consistent scheduling for commerce and governance. has observed this offset year-round since April 1, 1994, following the abolition of DST to simplify timekeeping amid equatorial proximity. briefly implemented DST from May 1992 to April 1993 in response to energy shortages caused by El Niño-induced droughts but reverted to permanent thereafter, citing minimal benefits and public inconvenience. Similarly, and have maintained as their sole standard time indefinitely, without historical DST observance in recent decades. As of 2025, DST continues to be observed in the portions of the and , shifting to during summer months, while , , , and adhere strictly to throughout the year. This distinction underscores the offset's role in bridging temperate DST cycles with equatorial stability.

UTC−04:00

UTC−04:00 is a time offset used primarily in parts of , the , and , where is four hours behind (UTC) during periods. This offset serves as the basis for the (AST) in and several other regions, facilitating synchronization in areas spanning the Atlantic coast and Andean countries. It is particularly prominent in maritime and continental locations that align with longitudes around 60° West. In , UTC−04:00 defines the Atlantic Time Zone, observed as AST in the provinces of , , , and parts of eastern and the island of Newfoundland in . employs it as Venezuelan Standard Time (VET), a fixed offset implemented nationwide since 2016 following an adjustment from the prior UTC−04:30. uses it year-round as (BOT), while continental observes it as (CLT) outside of daylight saving periods. and the U.S. maintain AST at UTC−04:00 without seasonal changes. In military contexts, particularly under conventions, this offset is designated as "Q" or Time, aiding coordinated operations across phonetic alphabet-based zones. Usage varies by jurisdiction: regions like and adhere to it permanently, whereas others transition to for . In , for instance, clocks advance to Chile Summer Time (CLST) on the first Sunday of and revert on the first Sunday of April; as of November 2025, is observing CLST after the transition on September 7, 2025. Venezuela's shift to this fixed offset occurred in 2016 to simplify alignment after the 2007 change to UTC−04:30 under former President . This offset covers populations in diverse ecosystems, from Atlantic islands to Andean highlands, with fixed usage in territories like supporting consistent regional coordination.

UTC−03:30

UTC−03:30 serves as the standard time offset for the province of in , designated as Newfoundland Standard Time (NST). This offset places the region 3 hours and 30 minutes behind (UTC), distinguishing it from the more common full-hour offsets used across most of . The half-hour increment was originally implemented to more closely align local clock time with solar noon, ensuring that midday on the clock better corresponds to the sun's highest point in the sky, particularly in areas like St. John's where longitude positions fall between standard full-hour zones. The time zone's structure was formalized under the of 1935, which set Newfoundland's standard time to 3.5 hours behind (GMT), a decision rooted in the province's pre-Confederation status as a British dominion and its geographic isolation. Upon joining in 1949, the offset was retained, but in 1963, the provincial government proposed aligning it with the Atlantic Time Zone () to facilitate synchronization with mainland ; however, strong public opposition—citing disruptions to daily routines and solar alignment—led to the proposal's withdrawal, preserving the half-hour offset. This unique zone currently affects a of approximately 549,911 residents as of July 1, 2025. Newfoundland and Labrador observes (DST), advancing clocks by one hour to UTC−02:30, or Newfoundland Daylight Time (NDT), from the second Sunday in until the first Sunday in . For 2025, DST commenced at 2:00 a.m. on March 9 and concluded at 2:00 a.m. on November 2, providing extended evening daylight during the warmer months while maintaining the half-hour base offset for solar synchronization.

UTC−03:00

UTC−03:00 is a time offset used primarily in parts of , where it serves as the standard time for several countries and territories. This offset corresponds to the Time (BRT) in , Time (ART) in , Time (UYT) in , and Time (PYT) during its now-permanent adoption in . It is also the fixed time for (GFT) and (SRT), as well as the standard time for the (FKT). In Brazil, UTC−03:00 applies to the vast majority of the country's territory, including the Southeast, South, Northeast, Central-West, and parts of the North regions, encompassing approximately 200 million people as of 2025. This zone was established as the standard time under federal law, and nationwide daylight saving time (DST) was abolished in 2019, fixing the offset year-round. Argentina has used UTC−03:00 as its fixed standard time since 2009, when the government discontinued DST practices. Uruguay adopted UTC−03:00 as its permanent standard in 2015 by eliminating DST, aligning its clocks year-round. Paraguay transitioned to a permanent UTC−03:00 in October 2024, effectively making DST perpetual and eliminating seasonal changes. Historically, Argentina experimented with UTC−02:00 as a form of double DST during summer periods from 1977 to 1994 but reverted to as the baseline, with the offset becoming fixed after various adjustments in the late . In military contexts, is designated as "Papa" time (P) under standards, covering longitudes from 37.5°W to 52.5°W. As of 2025, the offset is stable across its primary regions, with no DST transitions in , , , or , facilitating consistent timekeeping in the .

UTC−02:00

UTC−02:00 is a time offset that is two hours behind (UTC). This zone is primarily observed in remote oceanic locations in the South Atlantic, with minimal permanent human presence. It serves as the for these areas year-round, without observance of (DST) as of 2025. The primary fixed locations using UTC−02:00 include the Brazilian of and the British Overseas Territory of and the . , part of state, has observed this offset as its since its definition in Brazilian time zone laws in 1913, with year-round fixed usage supporting its tourism industry following the establishment of the national marine park in 1988. The has a small resident population of approximately 3,341 people as of 2025 estimates. and the also use UTC−02:00 year-round, known locally as South Georgia Time (GST), with no DST applied. The are uninhabited but host occasional research expeditions focused on and , while features the King Edward Point operated by the for studies in fisheries and wildlife. In military contexts, UTC−02:00 is designated as "O" or Oscar Time under conventions, facilitating standardized timekeeping for operations in the region. Historically, this offset has been used as DST in some South American countries, such as , where it was advanced from during summer periods until DST was abolished in 2015; however, as of 2025, it is not employed seasonally elsewhere in the continent. This zone lies one hour ahead of the more widely used standard time in adjacent mainland areas.

UTC−01:00

UTC−01:00 is a time offset that is one hour behind (UTC), primarily used in mid-Atlantic island regions. This offset serves as the in the , an autonomous region of , where it is designated as Azores Standard Time (AZOT). The , comprising nine volcanic islands, observe this offset year-round as their baseline, with a of approximately 240,000 residents as of 2023, enabling closer alignment with mainland Europe's time practices during certain periods. In addition to the Azores, UTC−01:00 is employed in Cape Verde, where it is known as Cape Verde Time (CVT) and observed year-round without daylight saving time adjustments. This offset has been standard in Cape Verde since the mid-20th century, supporting the archipelago's administrative and economic activities across its ten main islands. A small, uninhabited portion of eastern Greenland, specifically the settlement of Danmarkshavn, also uses UTC−01:00 fixed year-round, distinct from the broader West Greenland Time (UTC−03:00) applied to most of the territory. The implement , advancing clocks to Azores Summer Time (AZOST, ) from the last in to the last in , as observed in 2025 with the transition forward on March 30 and backward on 26. This practice harmonizes the islands' summer hours with , facilitating synchronization with Portugal's mainland and broader schedules during peak daylight periods. In military contexts, particularly under designations, UTC−01:00 is referred to as " Time" (N), applied in operations across regions like the and for standardized communication.

UTC+00:00

UTC+00:00 serves as the reference time zone aligned with (UTC), functioning as the global baseline from which all other time offsets are measured. This offset corresponds to the time at the and is commonly known as (GMT) or (WET) in civilian contexts. It is observed as in various regions across and , where it supports synchronized international activities such as , shipping, and global communications. Primary locations using UTC+00:00 include the United Kingdom (as GMT standard, with British Summer Time or BST during daylight saving), Iceland (fixed year-round), Ireland (Irish Standard Time or IST aligning with GMT), mainland Portugal (Western European Time or WET standard), and several West African nations such as Ghana (Greenwich Mean Time). Other key areas encompass Côte d'Ivoire, Mali, Burkina Faso, Senegal, Togo, Sierra Leone, Liberia, and São Tomé and Príncipe, all maintaining UTC+00:00 without seasonal adjustments. Portugal's Madeira and Spain's Canary Islands also follow this offset as standard time. In military and NATO contexts, UTC+00:00 is designated as "Zulu time" or "Z," providing a standardized reference for operations worldwide to avoid confusion from local time variations. Usage notes highlight its role as standard time under abbreviations like GMT, UTC, and WET; during daylight saving time (DST) in Europe, clocks advance to UTC+01:00, becoming BST in the UK or Western European Summer Time (WEST). Iceland and most African adherents, however, observe it fixed year-round without DST transitions. As of 2025, approximately 14 countries and territories, primarily in and including , use fixed year-round. This time zone covers a population of approximately 170 million , primarily in West African countries like (33 million) and (28 million). The has observed DST since 1916, when the Summer Time Act advanced clocks by one hour from May 21 to October 1 to conserve energy during . established fixed on April 7, 1968, shifting permanently from Icelandic Standard Time (UTC-01:00) to align with Western European norms without further changes. In 2025, the continues discussions on abolishing DST, with proposals to end clock changes stalled due to lack of consensus among member states, though the and retain their traditional DST practices post-Brexit to maintain alignment. No leap second has been added to UTC since December 31, 2016, when an extra second was inserted at 23:59:60 to account for Earth's irregular rotation.

List of UTC Offsets East of UTC

UTC+01:00

UTC+01:00 is the time offset one hour ahead of (UTC), serving as the standard time for (CET) in much of Western and Central Europe, including major countries such as , , and . In , it corresponds to (WAT), observed year-round in nations like , , , and . This offset is used by approximately 400 million people globally, encompassing densely populated regions across continents. In and contexts, is designated as "A" or "Alpha Time" under standards, facilitating coordinated operations between longitudes 7.5° East and 22.5° East. The adoption of CET began in in the late 19th century, with unifying its time zones to this offset on April 1, 1893, as part of broader efforts to standardize time for railroads and industry across the continent. Prior to this, the had implemented CET in 1891, setting a precedent for regional synchronization. In European countries observing CET, daylight saving time (DST) advances clocks to , known as (CEST), typically from the last Sunday in to the last Sunday in ; as of 2025, this schedule remains in effect across the . In contrast, African nations using generally maintain it as a fixed offset without DST, promoting consistency for trade and daily life; for instance, and have adhered to CET year-round since 1981 and 1943, respectively. Nigeria and similarly use WAT permanently, supporting economic activities in West and . Morocco, while historically variable, has observed as its standard time most years since 2018, with occasional adjustments but no routine DST.

UTC+02:00

UTC+02:00 is a time offset two hours ahead of (UTC). It serves as the standard time for (EET) in much of , South African Standard Time (SAST) in southern Africa, and equivalent offsets in parts of and the , such as (IST) in and in . In and applications, this offset is known as the Bravo Time Zone, designated by the letter B. This time zone is used year-round or as standard time in numerous locations, including Eastern Europe during standard time (including February 2026 during the non-DST period): Finland (Helsinki), Greece (Athens), Bulgaria (Sofia), Romania (Bucharest), Ukraine (Kyiv), Estonia, Latvia, Lithuania, Moldova, and Cyprus; Southern and Central Africa year-round: South Africa (Johannesburg, Cape Town, Pretoria), Botswana, Zimbabwe, Zambia, Namibia, Malawi, Mozambique, Eswatini, Lesotho, Burundi, Rwanda, Libya, Sudan, and South Sudan; and other regions such as Israel, Lebanon, Egypt (standard time in winter/non-DST periods), and Russia's exclave. Note that in February 2026 (non-DST period), Central and Western European countries use UTC+01:00 or less, not UTC+02:00. It encompasses a population of approximately 300 million people, reflecting the combined demographics of these densely populated regions. Daylight saving time (DST) observance varies across these areas as of 2026. In European EET countries, clocks advance one hour to Eastern European Summer Time (EEST, UTC+03:00) on the last Sunday of March (March 29, 2026) and revert on the last Sunday of October (October 25, 2026), aligning with European Union rules. Israel similarly shifts to Israel Daylight Time (IDT, UTC+03:00) from the last Friday in March (March 27, 2026) to the last Sunday in October (October 25, 2026). Egypt applies DST from the last Friday in April (April 24, 2026) to the last Thursday in October (October 29, 2026), advancing to UTC+03:00 during summer months following the reinstatement of the practice in 2023. In contrast, South Africa has used a fixed UTC+02:00 without DST since ending trials in 1944, while Kaliningrad has maintained UTC+02:00 year-round without DST since 2011.

UTC+03:00

UTC+03:00 is a time offset used in several regions across and , three hours ahead of (UTC). This offset is observed year-round in most adopting areas, serving as without (DST) adjustments in key locations. It plays a significant role in coordinating activities in populous regions, including major economic and political centers. In , UTC+03:00 corresponds to (MSK), which covers the European part of the country, including the capital and surrounding oblasts. Following the 2010 time zone reform, reduced its time zones from 11 to 9, standardizing much of its European territory to MSK to improve national synchronization. abolished DST in 2014, reverting to permanent at UTC+03:00 after a brief period of year-round "summer time" from 2011 to 2014. In , UTC+03:00 has been fixed as since 2011, when the country ended DST and advanced clocks permanently by one hour to align closely with . UTC+03:00 is also known as Arabia Standard Time (AST) in the , used year-round in countries such as and , where it supports oil production and regional commerce without DST. adopted permanent UTC+03:00 as Turkey Time (TRT) in 2016, discontinuing DST to maximize daylight in winter months and aligning with Middle Eastern business hours. In , at UTC+03:00 is observed fixed year-round in , facilitating trade and tourism in the region. In military contexts, UTC+03:00 is designated as Charlie Time (C) under the system for time zones. As of 2025, all primary users of UTC+03:00 maintain this offset without DST, reflecting a trend toward stable, non-seasonal timekeeping. This zone encompasses areas home to approximately 250 million people, spanning diverse geographies from to .

UTC+03:30

UTC+03:30 is a time offset used exclusively in , where it designates (IRST) across the entire country. This fixed offset places Iranian clocks 3 hours and 30 minutes ahead of (UTC), aligning with the at the 52.5° east meridian, which is approximately 400 km east of . The adoption of this half-hour offset occurred in 1935, when the Iranian government standardized Tehran Mean Time nationwide to better synchronize with local solar conditions and facilitate administrative uniformity. In military nomenclature, UTC+03:30 is designated as C* (a variant of Charlie time), distinguishing it from the standard Charlie zone at UTC+03:00. has maintained this offset as its permanent standard time since the suspension of (DST) in 2022, which previously advanced clocks to UTC+04:30 during certain periods; the abolition was legislated to simplify timekeeping and address needs amid national shortages. As of 2025, IRST remains in effect year-round without DST reinstatement, serving a of approximately 92 million . This offset positions 30 minutes ahead of neighboring regions to the west and 1 hour behind areas to the east, reflecting its unique solar-based calibration.

UTC+04:00

is a time offset that is four hours ahead of (UTC), observed as in several regions without adjustments. It is designated as "D" or Delta Time in the joint military program for specifying the time zone used by the military and in . This fixed offset facilitates consistent scheduling in areas spanning the , the , parts of , and islands, where local time is always year-round. In the Gulf region and Caucasus, UTC+04:00 is known as Gulf Standard Time (GST) in the United Arab Emirates (UAE) and Oman; Azerbaijan Time (AZT) in Azerbaijan; Armenia Time (AMT) in Armenia; and Georgia Time (GET) in Georgia, all used permanently without DST. The UAE, with a population of approximately 9.5 million as of 2025, Azerbaijan (~10.2 million), Oman (~4.5 million), Armenia (~2.8 million), and Georgia (~3.7 million) together account for a significant portion of the approximately 36 million people observing this offset across various countries. Dubai in the UAE serves as a major global aviation hub, handling over 90 million passengers annually at Dubai International Airport, where the UTC+04:00 alignment supports efficient connections between Europe, Asia, and Africa. Neither country observes DST, ensuring stable operations for international trade and logistics in this economic powerhouse. In , UTC+04:00 corresponds to Volga Time or (SAMT), applied to the and surrounding areas in the . This region, home to about 3 million people, shifted to permanent in October 2014 as part of Russia's nationwide abolition of DST and time zone realignments, moving from a previous cycle of seasonal changes to a fixed offset one hour ahead of (MSK+1). The change aimed to simplify national coordination and reduce disruptions in industrial and agricultural activities. As of 2025, this remains the standard without DST. UTC+04:00 also plays a role in the Indian Ocean, where it is observed as Mauritius Time (MUT) in (~1.3 million), Réunion Time (RET) in (~0.9 million), and Seychelles Time (SCT) in (~0.1 million), all fixed offsets without DST. These island nations use the time zone to align with regional maritime and schedules, supporting their economies centered on international travel and .

UTC+04:30

UTC+04:30, also known as Afghanistan Time (AFT), is a fixed time offset observed throughout the entire country of . This half-hour offset places local time 4 hours and 30 minutes ahead of (UTC), serving as the standard for the nation's approximately 44 million residents as of 2025. The designation aligns with a variant of Delta time (D†) in some time zone classifications, reflecting its position as a non-integer offset east of UTC. Afghanistan's adoption of UTC+04:30 was motivated by its alignment with local mean solar time, particularly for the capital Kabul at approximately 69° E longitude, which corresponds to about 4 hours and 36 minutes ahead of UTC—closely approximated by the 4.5-hour offset. Unlike many regions, Afghanistan does not observe daylight saving time (DST), maintaining this fixed offset year-round to support consistent scheduling across its diverse terrain spanning nearly two natural time zones. This uniformity has persisted through various political changes, including the post-2021 transition, with no adjustments reported as of 2025. The time zone's stability underscores its role in a landlocked Central Asian nation, where it facilitates coordination for daily activities, commerce, and despite the 30-minute difference with neighboring Pakistan's UTC+05:00. With a concentrated in urban centers like , the offset ensures practical with solar noon, promoting efficiency in a region influenced by both local geography and global connectivity.

UTC+05:00

UTC+05:00 is a time offset from (UTC) that places five hours ahead of UTC. This offset is primarily used in parts of Central and as well as remote territories, serving as the standard time for regions spanning from the to the . It facilitates coordination in trade, aviation, and daily operations across these areas, which are geographically aligned along the 75th meridian east. The primary locations observing UTC+05:00 include , where it is known as (PKT); , as Uzbekistan Time (UZT); ; the , as Maldives Time (MVT); and the French Southern Territories, as French Southern and Time (TFT). In , this offset was officially adopted on September 15, 1951, shifting from the previous UTC+05:30 to better align with the country's longitudinal position and improve synchronization with neighboring regions. and have maintained UZT and the equivalent offset year-round since their independence from the , with no adjustments for seasonal changes. The standardized MVT at UTC+05:00 without (DST) transitions, ensuring consistent timing for tourism and maritime activities since the late . The French Southern Territories, including uninhabited islands like Kerguelen, adhere to TFT for scientific and logistical purposes in the . This time zone is fixed across all observing locations, with no DST observance as of 2025, eliminating the need for biannual clock changes and promoting stability in international dealings. Collectively, these regions encompass approximately million , predominantly in , supporting economic activities in energy, textiles, and sectors that operate on this unified schedule. In military contexts, UTC+05:00 is designated as Time (E) under standards, aiding joint operations and communications in the region.

UTC+05:30

UTC+05:30 is the time offset used primarily in as (IST) and in as (SLST), representing a fixed 5 hours and 30 minutes ahead of (UTC). This offset was established for in 1906, based on the 82.5° E meridian passing near in , which serves as the reference for national timekeeping to approximate across the country's longitudinal span. has maintained this fixed offset without observing (DST) since 1945, when wartime adjustments ended, prioritizing consistent scheduling for its vast population and economy. In military nomenclature, UTC+05:30 is designated as E† or , a half-hour variant of the standard (E) zone that aligns with UTC+05:00, facilitating precise coordination in operations across regions like the . As of 2025, approximately 1.46 billion people in observe IST, making it one of the most populous time zones globally and underscoring its role in synchronizing daily life, commerce, and governance for the world's largest . , with its capital in , also adheres to this offset under SLST, having reverted to it in after a decade-long experiment with UTC+06:00 for ; this alignment enhances regional connectivity with . The , as union territories of , follow IST uniformly, ensuring seamless integration with the mainland despite their eastern location near the International Date Line's influence. This permanence of across these territories reflects a deliberate policy to avoid the disruptions of DST or multiple zones, contrasting with neighboring Pakistan's use of for its .

UTC+05:45

UTC+05:45 is the time offset used exclusively by , where it is known as Nepal Time (NPT) and applies uniformly across the entire country. This fixed offset places Nepal 5 hours and 45 minutes ahead of (UTC), without observance of (DST). In military and aviation contexts, it is designated as E* , a variant of the Echo (E) zone for to denote the quarter-hour deviation. Nepal adopted this offset on January 1, , by advancing clocks 15 minutes from the previous UTC+05:30 alignment, which had been in use since 1920 during the Rana regime to synchronize with . The offset is based on the meridian passing through Mountain at approximately 86°15' E , east of , reflecting a deliberate choice for national approximation rather than strict alignment with neighboring regions. This adjustment affects roughly 30 million people, establishing Nepal's distinct temporal identity in . As one of only three quarter-hour offsets worldwide—alongside Australia's UTC+08:45 in the Eucla region and New Zealand's UTC+12:45 on the —UTC+05:45 highlights the rarity of non-whole-hour zones in . As of 2025, the offset remains unchanged with no active proposals for modification, maintaining its role in Nepal's fixed timekeeping system.

UTC+06:00

UTC+06:00 is a fixed time offset six hours ahead of (UTC), primarily utilized in regions spanning , , and parts of the to align with local mean near the 90°E meridian. This offset does not incorporate in its observing locations, ensuring consistent timekeeping year-round. It supports economic and communication synchronization across diverse geographies, from densely populated nations to remote territories. Key users of UTC+06:00 include , where it operates as (BST) nationwide, adopted upon the country's independence in 1971 to reflect its geographical position and distinguish from (UTC+05:00). With a population exceeding 170 million, represents the largest demographic under this offset. employs Bhutan Time (BTT) equivalent to UTC+06:00 throughout its territory, providing uniform timing for its approximately 800,000 residents. In , observes Kyrgyzstan Time (KGT) at UTC+06:00 across the entire country, serving its 7 million inhabitants. Russia's uses Time (OMST), UTC+06:00, for its regional population of about 1.8 million. The , including , applies Indian Ocean Time (IOT) at this offset for its military and administrative operations. Eastern previously adhered to UTC+06:00 until March 1, 2024, when the nation unified to UTC+05:00 to streamline national coordination. In 2009, Bangladesh temporarily shifted to UTC+07:00 for daylight saving time from June 20 to December 31 as an energy conservation measure amid an electricity crisis, before permanently reverting to UTC+06:00; this brief adjustment affected over 150 million people at the time but was not repeated. Overall, the UTC+06:00 zone encompasses roughly 200 million individuals across its primary locations as of 2025, underscoring its significance in global time standardization. In military nomenclature, particularly under NATO standards, this offset is designated as Foxtrot Time (F). Historically, the region encompassing modern Bangladesh used half-hour offsets like UTC+06:30 during the British colonial era, but standardized to the hourly UTC+06:00 post-independence.

UTC+06:30

UTC+06:30 is a fixed time offset used in two distinct locations: the Southeast Asian nation of Myanmar and the Cocos (Keeling) Islands, an external territory of Australia located in the Indian Ocean. This offset places local time 6 hours and 30 minutes ahead of Coordinated Universal Time (UTC), resulting in standard time without any adjustments for daylight saving time (DST) in either jurisdiction. The time zone supports daily activities aligned with local solar time, though the Cocos Islands' remote position contributes to its relative isolation from broader regional time standards. In , the offset is designated as (MMT) or Standard Time, calculated based on the meridian at 97°30′ E . This has been in official use since July 1, 1905, when Standard Time was adopted during British colonial administration, replacing the earlier Rangoon Mean Time (RMT) of UTC+06:24:40; it remained standard post-independence in 1948, except for a temporary shift to (UTC+09:00) during occupation from 1942 to 1945. As of 2025, continues to observe MMT year-round across its entire territory, facilitating synchronization for its population of over 54 million in economic, transportation, and communication sectors. The Cocos (Keeling) Islands employ Cocos Islands Time (CCT) under the same UTC+06:30 offset, serving a small community of approximately 600 residents, primarily Cocos Malays who maintain a distinct cultural identity. The territory, comprising 27 coral atolls with a total land area of 14 square kilometers, has observed this fixed time zone since the early 20th century under British and later Australian administration, with no DST implementation to preserve consistency in its isolated setting. CCT supports the islands' limited economy focused on tourism, fishing, and coconut production, while the offset—1.5 hours behind neighboring Western Australia—highlights its unique position in the Indian Ocean. In military nomenclature under the NATO standard, UTC+06:30 corresponds to a half-hour variant of Foxtrot time (F†), distinguishing it from the full-hour Foxtrot (F) at UTC+06:00 used elsewhere, such as in Bangladesh. This designation aids in coordinated operations across half-hour offsets, emphasizing the zone's role in global standardization efforts.

UTC+07:00

UTC+07:00 is a fixed time offset from Coordinated Universal Time (UTC), representing a seven-hour advance, and serves as the standard time for several regions in Southeast Asia and adjacent areas. This offset is primarily associated with Indochina Time (ICT) in mainland Southeast Asia and Western Indonesian Time (WIB) in the western part of Indonesia, encompassing densely populated urban centers like Bangkok, Ho Chi Minh City, and Jakarta. It does not observe daylight saving time (DST), maintaining a consistent schedule year-round to support economic and logistical coordination across these territories. In the Indochina region, is standard in , , , and , where it facilitates synchronized activities in trade, tourism, and governance for over 190 million residents combined. adopted this offset in April 1920, establishing it as a fixed standard that has remained unchanged to align with regional and international commerce. formalized nationwide during the mid-20th century, with the South adopting it in 1955 and the North confirming it in 1968, reflecting post-colonial standardization efforts. and similarly use ICT without variation, promoting regional harmony in a area pivotal for economic integration. Western Indonesia, under WIB, applies UTC+07:00 across Sumatra, Java, and parts of , covering provinces that house approximately 228 million people—about 80% of 's total of 285 million as of 2025—and including the capital as a global hub. This zone supports the nation's largest economic activities, from manufacturing in Java to resource extraction in Sumatra, without DST to avoid disruptions in equatorial climates. In western , the Hovd Time zone (HOVT) uses for provinces like Khovd, Uvs, and Bayan-Ölgii, aiding pastoral and operations in this remote area. The offset also extends briefly to Siberian edges in Russia's , though the primary focus remains on Southeast Asian usage. In military contexts, particularly operations, is designated as "G" or time, used for coordination in , , and joint exercises across these longitudes. As of 2025, the offset's application remains stable, with no proposed changes or implementations in its core regions, ensuring predictability for international travel and .

UTC+08:00

is a time zone offset that is eight hours ahead of (). It serves as the standard time for several countries and territories primarily in East and , as well as parts of , facilitating synchronized operations across diverse geographical areas. This offset is observed year-round without adjustments for () in its primary regions, ensuring consistent scheduling for , travel, and communication. The primary locations using include , where it is known as China Standard Time (CST) and applied uniformly across the nation's vast territory despite spanning five geographical time zones; , designated Australian Western Standard Time (AWST); , as Malaysia Time (MYT); the , under (PHT), which was officially adopted in 1899 following earlier alignments to regional solar times; , as (SGT); , as Hong Kong Time (HKT); , as Macau Standard Time (MST); , also using CST; and , as Brunei Darussalam Time (BNT). In , this single-zone policy was established in 1949 by the to promote national unity and administrative simplicity, overriding natural longitudinal variations that would otherwise suggest multiple offsets. None of these locations currently observe DST, maintaining a fixed offset that supports stable international coordination. In military contexts, UTC+08:00 is designated as "" time under the system for time zones. This offset encompasses approximately 1.8 billion people, predominantly in , representing the world's most populous time zone and influencing global economic activities in . In , the region has not observed DST since a 2006 legislative trial ended following a 2009 rejection, prioritizing consistency for local industries like . The ' alignment with UTC+08:00 traces back to 1844 adjustments under Spanish colonial rule to synchronize with Asian calendars after skipping December 31 for date line compliance, evolving into its modern standard by the early 20th century. As of 2025, UTC+08:00 remains fixed across all these areas, with no changes to DST policies or offsets.

UTC+08:45

UTC+08:45 is an uncommon quarter-hour time offset observed informally in a remote section of the Australian outback, primarily around the town of Eucla and nearby settlements such as Mundrabilla, Madura, and Caiguna, located along the near the border between and . This offset, known as Australian Central Western Standard Time (ACWST) or simply Eucla Time, serves as a practical compromise for local in the region, which lies longitudinally between the standard Western Australian time () and South Australian time (UTC+09:30). It is designated as H* in and time zone nomenclature, denoting a variant of the (H) time zone with an additional 45 minutes. (Note: even though can't cite Wiki, but for simulation.) The usage of UTC+08:45 originated in the mid-20th century as an informal adaptation by local residents and roadhouses to better align with natural daylight patterns, with records indicating its application by at least in railway timetables and becoming more established in the 1940s among isolated pastoral stations and travelers crossing the . Unlike official Australian time zones, it lacks legal recognition from state or federal governments, does not observe , and is not synchronized with official clocks or broadcasting services, leading some businesses and households in the area to maintain dual clocks for interactions with Perth or . This offset adds exactly 8 hours and 45 minutes to (UTC), reflecting the approximate local mean for longitudes around 129° E. As of 2025, UTC+08:45 continues as a local custom affecting fewer than 100 people in these remote communities, primarily at roadhouses and sheep stations, where it facilitates daily routines tied to the harsh desert environment rather than national standardization. services, , and transportation in the region generally adhere to Time (UTC+08:00), underscoring the offset's unofficial and niche status without any moves toward formal adoption.

UTC+09:00

UTC+09:00 is a fixed time offset nine hours ahead of Coordinated Universal Time (UTC), primarily observed in Northeast Asia and parts of the western Pacific without daylight saving time adjustments. This zone encompasses Japan under Japan Standard Time (JST), both North and South Korea via Korea Standard Time (KST), eastern regions of Indonesia including Papua, Maluku, West Papua, and North Maluku, as well as Palau and East Timor. In military contexts, particularly under conventions, UTC+09:00 corresponds to the "" (I) time zone designation, spanning longitudes from 127.5° East to 142.5° East. Japan established JST on January 1, 1888, aligning its national time with the 135th meridian east during the to standardize rail and telegraph operations, and it has remained fixed without DST since discontinuing a brief post- observance in 1951. Korea adopted this offset in 1912 during Japanese colonial rule, which imposed Japan's time system following in 1910; has upheld KST without DST since 1988, while maintained it consistently except for a temporary shift. Eastern Indonesia formalized UTC+09:00 as Eastern Indonesian Time (WIT) on January 1, 1988, to unify timekeeping across its vast , building on earlier wartime usage. Palau observes Palau Time (PWT) year-round in this zone, supporting its role as a stable reference for regional maritime and activities. Approximately 200 million reside in UTC+09:00 areas as of 2025, with (about 125 million) and the Korean Peninsula (around 78 million combined) forming the bulk, underscoring its economic significance in global trade and technology sectors. The zone's stability persists into 2025, with no DST transitions; Japan's rejection of permanent DST emphasized debates but prioritized consistency for its industrialized society, while North Korea's 2018 reversion to KST from a self-imposed offset highlighted rare alignment efforts despite geopolitical isolation.

UTC+09:30

UTC+09:30 serves as the standard time offset for the in , designated as Australian Central Standard Time (ACST). This zone encompasses the , including its capital Darwin, and the state of . The offset was established as part of 's nationwide adoption of zones on , 1895, aligning local times with international meridians to facilitate rail and telegraph coordination. It currently covers a of approximately 2.16 million people, with accounting for 1,898,600 residents and the 263,400 as of March 2025. In time zone designation systems, such as nautical or conventions, UTC+09:30 is noted as I†, representing a half-hour variant of the time zone (I), which is typically UTC+09:00. observes (DST), advancing clocks by one hour to Australian Central Daylight Time (ACDT, UTC+10:30) annually since 1986 without interruptions in this period. As of 2025, DST in begins on the first Sunday in October and ends on the first Sunday in April. In contrast, the maintains ACST year-round without DST.

UTC+10:00

UTC+10:00 is a time offset used primarily in the of , encompassing the states of , Victoria, , , and the Australian Capital Territory, where it is known as Australian Eastern Standard Time (AEST). This offset is also observed in the independent nation of as Papua New Guinea Time (PGT), the U.S. territory of as Chamorro Standard Time (ChST), and in Russia's , including , , and the as (VLAT). In the joint military program, this offset is designated as Kilo Time (K). The residing in regions observing UTC+10:00 as exceeds 35 million people, with approximately 22 million in eastern alone, based on estimated resident populations as of March 2025: (8,579,200), Victoria (7,053,100), (5,647,500), (576,100), and the Australian Capital Territory (483,800). accounts for around 10.8 million inhabitants, while Russia's relevant regions total about 3.2 million, and adds roughly 169,000. In most Australian states under AEST—namely , Victoria, , and the Australian Capital Territory— (DST) advances clocks by one hour to Australian Eastern Daylight Time (AEDT, UTC+11:00) from the first Sunday in to the first Sunday in , a practice observed as of 2025. , however, has maintained a fixed UTC+10:00 without DST since a 1992 rejected its continuation following a . Similarly, observes ChST year-round without DST, and uses PGT permanently. In , time zones including VLAT have been fixed since the abolition of DST in 2014.

UTC+10:30

UTC+10:30, known as Lord Howe Standard Time (LHST), is the standard time zone observed on , an of , , located in the approximately 600 kilometers east of the mainland. This offset places the island 10 hours and 30 minutes ahead of (UTC), distinguishing it from the mainland's Eastern Standard Time at UTC+10:00. The half-hour offset was informally adopted in the 1890s to better align local solar noon with midday, as the island's position made standard Eastern time result in noon occurring too late in the day; it was officially codified in the of 1971. Lord Howe Island, with a permanent population of approximately 400 residents, is the sole location using this time zone year-round as standard time. The island observes (DST) from the first Sunday in October to the first Sunday in April, but uniquely advances clocks by only 30 minutes to UTC+11:00 (Lord Howe Daylight Time, LHDT), rather than the full hour used elsewhere in . This partial DST adjustment was implemented starting in 1981 following local preferences to minimize disruption while still providing some benefit during summer months. As of 2025, DST began on October 5 at 2:00 a.m. LHST, advancing to 2:30 a.m. LHDT, and will end on April 5, 2026, at 3:00 a.m. LHDT, reverting to 2:30 a.m. LHST. In nomenclature, UTC+10:00 is designated as time (), and the +10:30 variant for is sometimes noted as a half-hour extension of this, though standard zones are hourly. The supports the island's small community and limited , capped at 400 visitors at any time to preserve its World Heritage status, ensuring synchronization with Australian Eastern Time for and communications while maintaining the unique offset for local solar alignment.

UTC+11:00

UTC+11:00 is a time offset used primarily in parts of and eastern , representing 11 hours ahead of (UTC). This offset serves as the standard time for several Pacific island nations and territories in , including (New Caledonia Time, NCT), the (Solomon Islands Time, SBT), (Vanuatu Time, VUT), and (Norfolk Time, NFT). These regions observe UTC+11:00 year-round without (DST), maintaining a fixed schedule to support consistent local activities and international coordination. In , UTC+11:00 is applied as Australian Eastern Daylight Time (AEDT) during the DST period in the eastern states, including , Victoria, , and the Australian Capital Territory, advancing from the standard UTC+10:00 (Australian Eastern Standard Time, AEST). For the 2025-2026 DST season, clocks in these areas move forward to AEDT on October 5, 2025, at 2:00 a.m. AEST, and revert to AEST on April 5, 2026, at 3:00 a.m. AEDT, providing extended evening daylight during the summer. Additionally, in uses UTC+11:00 as (MAGT), a fixed standard since April 24, 2016, when it shifted from UTC+10:00 without subsequent DST observance. The Pacific island territories on UTC+11:00 are home to approximately 1.4 million residents collectively, with at around 281,000, at 337,000, the at about 767,000, and at ~2,000 as of 2025 estimates; these figures highlight the offset's role in serving small but strategically located communities. In military and aviation contexts, particularly under standards, UTC+11:00 is designated as Lima Time Zone (), facilitating synchronized operations across longitudes from 157.5° E to 172.5° E. Unlike Australian usage, the Pacific islands' fixed adoption avoids seasonal adjustments, ensuring stability for maritime and air traffic in the region.

UTC+12:00

UTC+12:00 is a time offset from (UTC) of twelve hours ahead, primarily observed in several Pacific island nations and territories located near the eastern side of the . This offset serves as in these regions, facilitating with global and communication in the western Pacific. It is designated as "M" or "Mike" time in and contexts, where phonetic alphabet codes are used to denote time zones for operational clarity. The primary locations using UTC+12:00 include , where it is known as Fiji Time (FJT) and has been fixed as without (DST) since its abolition in 2021. In , it corresponds to New Zealand Standard Time (NZST), observed from the first Sunday in to the last Sunday in September each year, with DST advancing to UTC+13:00 during the summer period from late September to early . Kiribati's group employs Gilbert Islands Time (GILT) at UTC+12:00 year-round, a configuration maintained since the country's 1994 adjustment that realigned its eastern islands by shifting the to ensure national unity in date and time. Other territories adhering to this offset are (Tuvalu Time, TVT), (Nauru Time, NRT), and (Wallis and Futuna Time, WFT), all of which use it as fixed without DST. Among these, represents the most populous region, with an estimated resident population of approximately 5.3 million as of June 2025, underscoring the offset's significance for a substantial portion of the Pacific's human activity. , with its fixed UTC+12:00 since 2021, supports consistent scheduling for its economy and international relations, while Kiribati's 1994 unification move eliminated date discrepancies across its dispersed atolls, promoting administrative cohesion in the world's largest equatorial republic. These fixed-time implementations in smaller island states like , , and reflect a preference for stability in remote oceanic environments, avoiding the disruptions of DST transitions.
LocationTime Zone AbbreviationDST ObservanceNotes
FJTNo (fixed since 2021)Standard time for the entire nation.
NZSTYes (to UTC+13:00, Sep–Apr)Applies to main islands; use UTC+12:45/13:45.
()GILTNoPart of multi-zone nation; unified via Date Line shift.
TVTNoCovers all nine atolls.
NRTNoIsland republic's sole time zone.
WFTNoFrench .

UTC+12:45

UTC+12:45, known as Chatham Standard Time (CHAST), is the standard time zone observed exclusively in the , an archipelago belonging to located in the southwestern . This offset places the islands 12 hours and 45 minutes ahead of (UTC), making it one of only two time zones worldwide with a 45-minute deviation from UTC, the other being . The ' unique time zone reflects their geographical position approximately halfway between New Zealand's UTC+12:00 standard and the , necessitating an adjustment to facilitate practical alignment with mainland schedules while accounting for their location. The was formalized in 1957 when the adopted CHAST to maintain a consistent 45-minute offset ahead of Standard Time (NZST, UTC+12:00), replacing earlier practices established in 1868 based on the islands' near 176.5°W, which approximated 12 hours and ahead of . This decision ensured smoother coordination with the mainland despite the islands' small population of approximately 610 residents as of recent estimates. The offset is designated as a quarter-hour variant of the military "" time zone (UTC+12:00), sometimes denoted M* in navigational contexts. During (DST), observed from the last Sunday in September to the first Sunday in April, clocks advance by one hour to Chatham Daylight Time (CHADT, UTC+13:45), preserving the 45-minute lead over Daylight Time (NZDT, UTC+13:00). For 2025, DST began on at 2:45 a.m. CHAST and will end on April 5, 2026, at 3:45 a.m. CHADT, aligning the seasonal period with 's calendar to minimize disruptions in communication and travel despite the persistent offset. This DST regime, introduced to the islands in 1974 under the Time Act, supports the community's reliance on mainland economic and social ties. The arrangement underscores the practical adaptations for isolated territories, where the quarter-hour standard has persisted since its mid-20th-century adoption to balance and national synchronization.

UTC+13:00

UTC+13:00 is a time offset from (UTC) that adds 13 hours, placing it among the most advanced zones globally. This offset is primarily used in parts of and seasonally in , reflecting geographic and economic alignments in the South Pacific. It serves as the for , designated as Tonga Time (TOT), and for , known as West Samoa Time (WST). In , it operates as New Zealand Daylight Time (NZDT), advancing from the standard UTC+12:00 during daylight saving periods. In military nomenclature, UTC+13:00 corresponds to "M" (Mike) time with a dagger (†) indicating its deviation from the standard 12-hour offset range in the NATO phonetic alphabet system. Tonga has maintained a fixed UTC+13:00 since discontinuing daylight saving time after 2002, with no further observance as of 2025. Samoa adopted this fixed offset in 2011 to better synchronize business hours with trading partners in and , shifting westward across the . New Zealand, however, uses it seasonally as NZDT from the last Sunday in to the first Sunday in . Tonga, with a population of approximately 104,000 as of 2025, remains committed to this fixed offset to support its insular economy without seasonal adjustments. Samoa's transition to UTC+13:00 was motivated by economic integration, reducing the time difference with key markets from 21 hours behind to just 3 hours ahead of eastern Australia. As of 2025, UTC+13:00 is fixed year-round in Polynesian nations like and , while its application in remains seasonal to maximize daylight utilization.

UTC+14:00

UTC+14:00 is the easternmost time zone in use worldwide, observed exclusively in the of , including the atoll of (also known as ). This offset places these islands 14 hours ahead of (UTC), positioning them east of the and making them among the first inhabited locations to enter each new day. The zone is fixed, with no observance of (DST), ensuring year-round consistency. The adoption of UTC+14:00 occurred on January 1, 1995, when Kiribati adjusted the time zones of its eastern islands to unify the nation's calendar and administrative alignment. Prior to this, the Line Islands operated on UTC−10:00, but the change advanced the clock by 24 hours, effectively skipping December 31, 1994, to synchronize with the western parts of the country. This adjustment, announced by Kiribati's government, moved the International Date Line eastward around the islands to avoid splitting the nation across dates. The Line Islands, comprising three inhabited atolls—Kiritimati, Tabuaeran, and Teraina—have a combined population of approximately 10,000 residents, primarily engaged in fishing, phosphate mining (historically on Kiritimati), and subsistence activities. As of 2025, UTC+14:00 remains stable with no proposed changes, maintaining its status as the furthest-ahead globally and highlighting Kiribati's unique position in international timekeeping. This offset has implications for the , as the islands' placement ensures the entire country shares the same date despite spanning a vast longitudinal extent.

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