Seychelles Time in the context of Arabia Standard Time

Greenwich Mean Time (GMT) is the local mean time at the Royal Observatory in Greenwich, London, counted from midnight. At different times in the past, it has been calculated in different ways, including being calculated from noon; as a consequence, it cannot be used to specify a particular time unless a context is given. The term "GMT" is also used as one of the names for the time zone UTC+00:00 and, in UK law, is the basis for civil time in the United Kingdom.

Because of Earth's uneven angular velocity in its elliptical orbit and its axial tilt, noon (12:00:00) GMT is rarely the exact moment the Sun crosses the Greenwich Meridian and reaches its highest point in the sky there. This event may occur up to 16 minutes before or after noon GMT, a discrepancy described by the equation of time. Noon GMT is the annual average (the arithmetic mean) moment of this event, which accounts for the word "mean" in "Greenwich Mean Time".

Eastern European Time (EET) is one of the names of the UTC+02:00 time zone, 2 hours ahead of Coordinated Universal Time. The zone uses daylight saving time, so that it uses UTC+03:00 during the summer.

A number of African countries use UTC+02:00 all year long, where it is called Central Africa Time (CAT), although Egypt and Libya also use the term Eastern European Time.

Azerbaijan Time (AZT) is the standard time zone in Azerbaijan, four hours ahead of UTC (UTC+04:00). The daylight saving time adjustment, Azerbaijan Summer Time (AZST), was one hour ahead at UTC+05:00; it was introduced in 1997 and discontinued in March 2016.

Azerbaijan Time is the same as Samara Time (Russia), United Arab Emirates Standard Time, Georgia Time, Armenia Time and Seychelles Time.

Africa, the world's second-largest and second-most populous continent, spans across six different time zone offsets from Coordinated Universal Time (UTC): UTC−01:00 to UTC+04:00. As Africa straddles the equator and tropics, there is little change in daylight hours throughout the year and as such daylight saving time is currently observed in only two countries, Morocco (year-round except Ramadan) and Egypt. However, it was previously observed in several other countries.

Before the wide adoption of standard time zones, local mean time was widely used in railway time for train timetables and telegraphic time for telegraphy. Local mean time is a solar time that corrects the variations of local apparent time by forming a uniform time scale at a specific longitude; for instance, Liberia observed UTC−0:44:30 instead of an approximate offset such as UTC−01:00. British Rhodesia (at the time administered by the private British South Africa Company) was the first area in Africa to adopt standard time, switching to UTC+02:30 on 1 August 1899 as the previous time standards proved problematic for the railway system. Other countries followed suit, and by 1912, most Portuguese, French and British territories had adopted a standard offset. Liberia was the last country in Africa to adopt a standard offset, doing so on 7 January 1972.

Cape Verde Time (CVT) is a time zone used by the Atlantic island nation of Cape Verde. The zone is one hour behind UTC (UTC−01:00).

This time zone applies all the year round. Due to its geographical location, completely west of the meridian 22°30'W (which forms the boundary between UTC−01:00 and UTC−02:00) Cape Verde effectively observes permanent daylight saving, given that the position of the archipelago is totally within the boundaries of UTC−02:00, the time zone observed until 1975.

West Africa Time, or WAT, is a time zone used in west-central Africa. West Africa Time is one hour ahead of Coordinated Universal Time (UTC+01:00), which aligns it with Central European Time (CET) during winter, and Western European Summer Time (WEST) / British Summer Time (BST) during summer.

As most of this time zone is in the tropical region, there is little change in day length throughout the year and therefore daylight saving time is not observed.

Central Africa Time or CAT, is a time zone used in north central, east central and southern Africa. Central Africa Time is two hours ahead of Coordinated Universal Time (UTC+02:00), which is the same as the adjacent South Africa Standard Time, Egypt Standard Time, Eastern European Time, Kaliningrad Time and Central European Summer Time.

As this time zone is in the equatorial and tropical regions, there is little change in day length throughout the year and so daylight saving time is not observed.

South African Standard Time (SAST) is the time zone used by all of South Africa as well as Eswatini and Lesotho. The zone is two hours ahead of UTC (UTC+02:00) and is the same as Central Africa Time. Daylight saving time is not observed in either time zone. Solar noon in this time zone occurs at 30° E in SAST, effectively making Pietermaritzburg at the correct solar noon point, with Johannesburg and Pretoria slightly west at 28° E and Durban slightly east at 31° E. Thus, most of South Africa's population experience true solar noon at approximately 12:00 daily.

The western Northern Cape and Western Cape differ, however. Everywhere on land west of 22°30′ E effectively experiences year-round daylight saving time because of its location in true UTC+01:00 but still being in South African Standard Time. Sunrise and sunset are thus relatively late in Cape Town, compared to the rest of the country.

Egypt Standard Time (EGY) (Arabic: توقيت مصر القياسي Tawqīt Miṣr al-qiyāsiyy) is UTC+02:00, which is equivalent to Eastern European Time, Central Africa Time, South African Standard Time and Central European Summer Time, and is co-linear with neighbouring Libya and Sudan(Winter only). Egypt has used Eastern European Summer Time (UTC+03:00), during the summer periods from 1957 to 2010, 2014 to 2015, and since 2023.

East Africa Time (EAT) is a time zone used in eastern and central Africa, with a standard offset of UTC+03:00 from Coordinated Universal Time (UTC). It is one of the most widely used time zones in Africa, adopted by countries including Kenya, Tanzania, Uganda, Ethiopia, Somalia, and others. EAT does not observe daylight saving time (DST), maintaining a consistent offset year-round due to the region's equatorial proximity, which results in minimal variation in daylight hours. In the IANA time zone database, EAT is represented by the canonical identifier Africa/Nairobi, with aliases such as Africa/Kampala and Africa/Dar_es_Salaam.

The time zone is three hours ahead of UTC (UTC+03:00), which is the same as Moscow Time, Arabia Standard Time, Further-eastern European Time and Eastern European Summer Time.

Mauritius Time, or MUT, is the time zone used by the Indian Ocean island nation of Mauritius. The zone is four hours ahead of UTC (UTC+04:00).

Mauritius does not use daylight saving time; however, it has been used in the past. Daylight saving time was first introduced in Mauritius in 1982; however, it was discontinued the following year. It was re-introduced in 2008; however, it was not used in 2009 or since. In 2008, the period started at 2 am UTC+5 (1 am UTC+4) on 26 October 2008 (the last Sunday in October), and ended at 2 am UTC+5 (1 am UTC+4) on 29 March 2009 (the last Sunday in March). Mauritius is in the Southern Hemisphere, so summer begins towards the end of the year.

UTC+04:00 is an identifier for a time offset from UTC of +04:00. In ISO 8601, the associated time would be written as 2019-02-07T23:28:34+04:00. This time is used in: