This is a list of time zones from release 2024a of the tz database. [2]
This is a list of time zones from release 2024a of the tz database. [2]
Standard Time (STD) and Daylight Saving Time (DST) offsets from UTC in hours and minutes.
For zones in which Daylight Saving is not observed, the DST offset shown in this table is a simple duplication of the STD offset.
The UTC offsets are based on the current or upcoming database rules. This table does not attempt to document any of the historical data which resides in the database.
Time zone abbreviations for both Standard Time and Daylight Saving Time are shown exactly as they appear in the database. See strftime and its "%Z" field.
Some of zone records use 3 or 4 letter abbreviations that are tied to physical time zones, others use numeric UTC offsets.
| Region | Zones | Links | Total |
|---|---|---|---|
| Africa | 19 | 35 | 54 |
| America | 120 | 48 | 168 |
| Antarctica | 8 | 4 | 12 |
| Asia | 75 | 24 | 99 |
| Atlantic | 8 | 4 | 12 |
| Australia | 11 | 12 | 23 |
| Europe | 38 | 26 | 64 |
| Indian | 3 | 8 | 11 |
| Pacific | 30 | 14 | 44 |
| Etc | 28 | 7 | 35 |
| Other | 12 | 63 | 75 |
| Total | 352 | 245 | 597 |
| Source File | Zones | Links | Total |
|---|---|---|---|
| factory | 1 | 0 | 1 |
| africa | 20 | 0 | 20 |
| antarctica | 6 | 0 | 6 |
| asia | 59 | 0 | 59 |
| australasia | 39 | 0 | 39 |
| etcetera | 28 | 1 | 29 |
| europe | 69 | 0 | 69 |
| northamerica | 85 | 0 | 85 |
| southamerica | 45 | 0 | 45 |
| backward | 0 | 244 | 244 |
| Total | 352 | 245 | 597 |
A time zone is an area which observes a uniform standard time for legal, commercial and social purposes. Time zones tend to follow the boundaries between countries and their subdivisions instead of strictly following longitude, because it is convenient for areas in frequent communication to keep the same time.
Daylight saving time (DST), also referred to as daylight saving(s), daylight savings time, daylight time (United States and Canada), or summer time (United Kingdom, European Union, and others), is the practice of advancing clocks to make better use of the longer daylight available during summer, so that darkness falls at a later clock time. The typical implementation of DST is to set clocks forward by one hour in spring or late winter, and to set clocks back by one hour to standard time in the autumn (or fall in North American English, hence the mnemonic: "spring forward and fall back").
Australia uses three main time zones: Australian Eastern Standard Time, Australian Central Standard Time and Australian Western Standard Time.
The time in China follows a single standard time offset of UTC+08:00 based on the National Time Service Center of Chinese Academy of Sciences located in Mount Li, Lintong District, Xi'an City, Shaanxi Province, even though the country spans almost five geographical time zones. The official national standard time is called Beijing Time domestically because based on 120th meridian east that Beijing City is located, and China Standard Time (CST) internationally. Daylight saving time has not been observed since 1991. China Standard Time (UTC+8) is consistent across Mainland China, Hong Kong, Macau, Taiwan, as well as equivalent with Philippines, Singapore, Brunei, most of Mongolia, Malaysia, Irkutsk Time (Russia), Western Australia and Central Indonesia.
There are eleven time zones in Russia, which currently observe times ranging from UTC+02:00 to UTC+12:00. Daylight saving time (DST) has not been used in Russia since 26 October 2014. From 27 March 2011 to 26 October 2014, permanent DST was used.
Time in Chile is divided into three time zones. Most of Continental Chile uses the time offset UTC−04:00 in winter time and UTC−03:00 in summer time, while the Magallanes and Chilean Antarctica region uses the time offset UTC−03:00 the whole year. Additionally, Easter Island uses the time offset UTC−06:00 in winter time and UTC−05:00 in summer time.
Argentina is located at a longitude that would naturally put it in the UTC−04:00 or UTC−05:00 time zone; however, it actually uses the UTC−03:00 time zone. Argentina determines whether to change clocks in observation of daylight saving time on a year-by-year basis, and individual provinces may opt out of the federal decision. At present, Argentina does not change clocks.
The tz database is a collaborative compilation of information about the world's time zones, primarily intended for use with computer programs and operating systems. Paul Eggert has been its editor and maintainer since 2005, with the organizational backing of ICANN. The tz database is also known as tzdata, the zoneinfo database or the IANA time zone database, and occasionally as the Olson database, referring to the founding contributor, Arthur David Olson.
The UTC offset is the difference in hours and minutes between Coordinated Universal Time (UTC) and local solar time, at a particular place. This difference is expressed with respect to UTC and is generally shown in the format ±[hh]:[mm], ±[hh][mm], or ±[hh]. So if the time being described is two hours ahead of UTC, the UTC offset would be "+02:00", "+0200", or simply "+02".
Iran Standard Time (IRST) or Iran Time (IT) is the time zone used in Iran. Iran uses a UTC offset UTC+03:30. IRST is defined by the 52.5 degrees east meridian, the same meridian which defines the Iranian calendar and is the official meridian of Iran.
The time zone in Germany is Central European Time and Central European Summer Time. Daylight saving time is observed from the last Sunday in March to the last Sunday in October. The doubled hour during the switch back to standard time is named 2A and 2B.
Bangladesh Standard Time is the time zone of Bangladesh. It is offset six hours ahead of Coordinated Universal Time, and observed as a national standard throughout the country. Bangladesh briefly observed daylight saving time (DST) in 2009 to cope with the ongoing electricity crisis, but in 2010 the decision was cancelled by the government of Bangladesh.
The time in Afghanistan follows a single standard time offset of UTC+04:30, even though the country spans almost two geographical time zones.
Daylight saving time (DST), also known as summer time, is the practice of advancing clocks during part of the year, typically by one hour around spring and summer, so that daylight ends at a later time of the day. As of 2024, DST is observed in most of Europe, most of North America and parts of Africa and Asia around the Northern Hemisphere summer, and in parts of South America and Oceania around the Southern Hemisphere summer. It was also formerly observed in other areas.
Switzerland uses Central European Time (CET) during the winter as standard time, which is one hour ahead of Coordinated Universal Time (UTC+01:00), and Central European Summer Time (CEST) during the summer as daylight saving time, which is two hours ahead of Coordinated Universal Time (UTC+02:00).
In Romania, the standard time is Eastern European Time. Daylight saving time, which moves one hour ahead to UTC+03:00 is observed from the last Sunday in March to the last Sunday in October.
The western African country Ghana observes a single time zone, denoted as Greenwich Mean Time. Ghana shares this time zone with several other countries, including fourteen in western Africa where it was formerly known as Western Sahara Standard Time (WSST). Ghana does not have an associated daylight saving time (DST). It previously observed DST as the erstwhile Gold Coast under British rule between 1919 and 1942, and 1950 and 1956.
Time in Liberia is given by a single time zone, denoted as Greenwich Mean Time. Liberia shares this time zone with several other countries, including fourteen in western Africa where it was formerly known as Western Sahara Standard Time (WSST). Liberia has never observed daylight saving time (DST).
Time in Ivory Coast is given by a single time zone, denoted as Greenwich Mean Time. Adopted on 1 January 1911, the Ivory Coast has never observed daylight saving time (DST).
Haiti observes Eastern Standard Time Zone (UTC−5) as standard time, and Eastern Daylight Time (UTC−4) as daylight saving time (DST). DST is observed annually from the second Sunday in March to the first Sunday in November.