Time zone · Africa
GMT
Greenwich Mean Time
Greenwich Mean Time (GMT) is the baseline from which every other timezone on the planet is measured, and most of its member zones in West Africa keep things refreshingly simple: no daylight saving adjustments and no clocks to change. Only six member zones change their clocks: the United Kingdom, Ireland, Guernsey, Jersey and the Isle of Man in summer, plus Antarctica's Troll station. The other 16 of the 22 zones — covering Ivory Coast, Ghana, Mali, Gambia, Guinea-Bissau, Guinea, Senegal, and Sierra Leone, among others — stay on GMT year-round.
Wednesday, October 14, 2026
Current offset
UTC+00:00
Standard · GMT
Daylight saving
Not active
Year-round standard time
IANA zones
22
6 observe DST, 16 don't
DST offset
UTC+01:00
IST · +1h
About GMT
Standard time, with a summer shift.
Greenwich Mean Time (GMT) is the baseline from which every other timezone on the planet is measured, and most of its member zones in West Africa keep things refreshingly simple: no daylight saving adjustments and no clocks to change. Only six member zones change their clocks: the United Kingdom, Ireland, Guernsey, Jersey and the Isle of Man in summer, plus Antarctica's Troll station. The other 16 of the 22 zones — covering Ivory Coast, Ghana, Mali, Gambia, Guinea-Bissau, Guinea, Senegal, and Sierra Leone, among others — stay on GMT year-round.
IANA zones · the technical identifiers
The 22 zones that resolve to GMT.
For software, always store the IANA identifier — never the abbreviation alone. The database keeps these zones distinct because their rules can, and historically did, diverge.
Cities across GMT
Local time, city by city.
37 cities
Where GMT is used
22 countries.
Same offset · UTC+00:00
Other zones at UTC+00:00 right now.
These named zones share GMT's offset today. When daylight saving rules differ, they drift apart for part of the year.
Convert
GMT to the world's clocks.
Frequently asked questions
Common questions about GMT, daylight saving, and how to handle it in software. Can't find what you need? Email [email protected].
- Why does GMT have so few DST-observing zones?
- Only 6 of GMT's 22 member zones observe daylight saving, mostly European territories; the majority in West Africa don't observe DST at all.
- Which countries share the same time as GMT year-round?
- Ivory Coast, Ghana, Mali, Gambia, Guinea-Bissau, Guinea, Senegal, Sierra Leone, Togo, Liberia, Mauritania, Burkina Faso, São Tomé and Príncipe, Iceland, Saint Helena and Greenland's Danmarkshavn station all stay on UTC+00:00 year-round.
- What is the significance of this region?
- GMT is mean solar time at the Prime Meridian in Greenwich, London, and was the world's reference time until it was replaced by Coordinated Universal Time (UTC), which is based on atomic clocks. For everyday purposes GMT and UTC show the same time.
- Do any GMT member zones observe DST?
- Yes. Six member zones (London, Dublin, Guernsey, Jersey, the Isle of Man, and Antarctica’s Troll station) leave GMT in summer, while the rest, from West Africa to Iceland, stay on it all year.
- What makes living in a non-DST timezone easier?
- Scheduling across borders is simplified when clocks never shift. Flights, meetings, and broadcasts need no seasonal adjustment, reducing confusion between regions.
- Can you give an example of a non-DST country in GMT?
- Ivory Coast is a year-round UTC+00:00 standard, with no daylight saving transitions. It has maintained this offset consistently since 1912.
Source: IANA tzdb2026d · Reviewed
Free · Developer API
This time zone, as JSON.
Its defining offset, DST status and member counts, from one endpoint.
Also in the API: time zones by coordinates, conversions that flag daylight saving gaps, and abbreviations decoded.
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