GMT to UTC Converter – Convert GMT to UTC

GMT and UTC share the same UTC+0 offset — no arithmetic is needed. A time in GMT is the same moment as the same clock reading in UTC.

UTC and GMT both use UTC+0 — they represent the same moment in time, with no offset between them. UTC is the modern international standard defined by atomic clocks; GMT is the historical astronomical standard. For everyday scheduling they are interchangeable. The only practical catch: the UK uses BST (UTC+1) during summer (last Sunday in March to last Sunday in October), so London time differs from GMT/UTC by 1 hour during that period.

GMT and UTC use the same UTC+0 offset, so there is no time difference to accommodate. Any time that works for one party works for the other. If the UTC side is in the UK during summer, remember to confirm whether London is on None (None) rather than GMT.

Yes. GMT (Greenwich Mean Time) observes Daylight Saving Time. Clocks spring forward to BST (UTC+1) on the last Sunday in March, and fall back to GMT on the last Sunday in October. During the DST period, the difference with UTC changes by 1 hour. In summer the UK switches to BST (British Summer Time, UTC+1). The GMT label itself never changes; it always means UTC+0. Our converter always uses the current offset for the date you select.

Major cities in the GMT (Greenwich Mean Time, UTC+0) timezone include: London (winter), Dublin (winter), Edinburgh, Reykjavik, Accra, Dakar. These cities switch to BST (UTC+1) from the last Sunday in March to the last Sunday in October.

Major cities in the UTC (Coordinated Universal Time, UTC+0) timezone include: UTC has no geographic location — it is the universal time reference used by aviation, the internet, meteorology, and global finance worldwide. UTC is a fixed-offset zone — these cities do not observe Daylight Saving Time.

GMT and UTC share the same UTC+0 offset — no adjustment is needed when scheduling. Simply agree on a time and it applies equally to both parties. If one party is in the UK during summer, confirm whether they are on None (None) to avoid a 1-hour mismatch. For full scheduling guidance, see our international meeting times guide.