GMT (Greenwich Mean Time) is UTC+0. It is the standard time of London, Dublin, Abidjan and Kumasi, which switch to BST for daylight saving time.
Where and when GMT is used
| IANA time zone | Uses GMT | Main cities |
|---|---|---|
| Europe/London | Outside daylight saving time | London, Birmingham, Glasgow |
| Europe/Dublin | Outside daylight saving time | Dublin, Cork, Limerick |
| Africa/Abidjan | All year | Abidjan, Abobo, Bouaké |
| Africa/Accra | All year | Kumasi, Accra, Tamale |
| Atlantic/Reykjavik | All year | Reykjavik |
GMT and BST
BST is the daylight saving version of GMT, 1 hour ahead of it. Writing GMT in summer means a time that is 1 hour off for the places that have switched.
Convert GMT to other time zones
Because GMT always means UTC+0, each row below is a fixed difference. Check the date only to know whether a place is on GMT at all.
| Zone | UTC offset | When it is 12:00 GMT |
|---|---|---|
| UTC | UTC+0 | 12:00 PM |
| EST | UTC−5 | 7:00 AM |
| EDT | UTC−4 | 8:00 AM |
| CST | UTC−6 | 6:00 AM |
| MST | UTC−7 | 5:00 AM |
| PST | UTC−8 | 4:00 AM |
| CET | UTC+1 | 1:00 PM |
| CEST | UTC+2 | 2:00 PM |
| EET | UTC+2 | 2:00 PM |
| MSK | UTC+3 | 3:00 PM |
| GST | UTC+4 | 4:00 PM |
| IST | UTC+5:30 | 5:30 PM |
| ICT | UTC+7 | 7:00 PM |
| JST | UTC+9 | 9:00 PM |
| AEST | UTC+10 | 10:00 PM |
| AEDT | UTC+11 | 11:00 PM |
Tools for time in GMT
- Convert a time to or from GMT: pick a date and time and see it in every city on your list.
- Add London to your world clock to keep it next to your own time.
- Find a meeting time that falls inside office hours in GMT and the other cities you work with.
- Open a full-screen clock for your own time zone.
Frequently asked questions
What is GMT in UTC?
GMT is UTC+0. To get UTC, nothing changes: GMT and UTC show the same time.
Is it GMT or BST right now?
GMT is in use now in London, Dublin, Abidjan and Kumasi. BST returns on Sunday, March 28, 2027.
What time is 12:00 GMT in UTC?
12:00 GMT is 12:00 PM UTC.
Time zone rules: IANA tz database, version 2026e. Place names and coordinates: GeoNames. Sunrise and sunset are calculated from the coordinates and can differ by a minute or two from local almanacs.