GMT time now (Greenwich Mean Time)
12:52PM
GMT · UTC+0
UTC+0+5 h vs New York (you)Europe/London
What GMT means
GMT stands for Greenwich Mean Time, UTC+0. It is the winter time of the United Kingdom and Ireland and the all-year time of Iceland and much of West Africa.
GMT in British law
In the United Kingdom, GMT is not just a name: an expression of time in an Act of Parliament “shall, unless it is otherwise specifically stated, be held to be Greenwich mean time” (Interpretation Act 1978, s. 9), subject to summer time under the Summer Time Act 1972. During summer time the legal time is one hour ahead of GMT, British Summer Time, from 1 a.m. GMT on the last Sunday of March to 1 a.m. GMT on the last Sunday of October.
So “London is on GMT” is true only in winter. Writing “GMT” for a London meeting in June places it an hour too early; “UK time” or Europe/London is the safe form.
GMT and UTC
For civil purposes GMT and UTC show the same time: since 1972 leap seconds have kept UTC within 0.9 seconds of UT1, the modern form of Greenwich mean solar time (NIST). The Summer Time Act still names GMT for astronomy, meteorology and navigation. Places that keep UTC+0 all year, such as Iceland, Ghana, Senegal and Côte d’Ivoire, are on “GMT” in tzdata’s wording; in summer the UK and Ireland move away from it, and so the gap between London and Reykjavík changes from zero to one hour.
Where and when GMT is used
5 zones use GMT all year. 2 zones use it for part of the year only, switching to daylight saving time in the other months. Computed from tzdata under the current rules.
| Main city | Time zone | Countries | When |
|---|---|---|---|
| London | Europe/London | United Kingdom, Guernsey, Isle of Man, Jersey | November to March |
| Abidjan | Africa/Abidjan | Ivory Coast, Burkina Faso, Ghana, Gambia, Guinea, Iceland, Mali, Mauritania, Saint Helena, Sierra Leone, Senegal, Togo | all year |
| Monrovia | Africa/Monrovia | Liberia | all year |
| Dublin | Europe/Dublin | Ireland | November to March |
| Bissau | Africa/Bissau | Guinea-Bissau | all year |
| São Tomé | Africa/Sao_Tome | Sao Tome and Principe | all year |
| Danmarkshavn | America/Danmarkshavn | Greenland | all year |
GMT converted to other zones
Every column is a fixed offset, so this table is valid on any date. Remember that the regions behind some columns switch to summer time (EST to EDT, CET to CEST, GMT to BST); the clock in those cities is then an hour later than the column.
| GMT (UTC+0) | EST (UTC−5) | PST (UTC−8) | CET (UTC+1) | IST (UTC+5:30) | JST (UTC+9) | AEST (UTC+10) | CST (UTC−6) |
|---|---|---|---|---|---|---|---|
| 12:00 AM | 7:00 PM (−1 day) | 4:00 PM (−1 day) | 1:00 AM | 5:30 AM | 9:00 AM | 10:00 AM | 6:00 PM (−1 day) |
| 6:00 AM | 1:00 AM | 10:00 PM (−1 day) | 7:00 AM | 11:30 AM | 3:00 PM | 4:00 PM | 12:00 AM |
| 9:00 AM | 4:00 AM | 1:00 AM | 10:00 AM | 2:30 PM | 6:00 PM | 7:00 PM | 3:00 AM |
| 12:00 PM | 7:00 AM | 4:00 AM | 1:00 PM | 5:30 PM | 9:00 PM | 10:00 PM | 6:00 AM |
| 3:00 PM | 10:00 AM | 7:00 AM | 4:00 PM | 8:30 PM | 12:00 AM (+1 day) | 1:00 AM (+1 day) | 9:00 AM |
| 6:00 PM | 1:00 PM | 10:00 AM | 7:00 PM | 11:30 PM | 3:00 AM (+1 day) | 4:00 AM (+1 day) | 12:00 PM |
| 9:00 PM | 4:00 PM | 1:00 PM | 10:00 PM | 2:30 AM (+1 day) | 6:00 AM (+1 day) | 7:00 AM (+1 day) | 3:00 PM |