GMT Time Now

What this page shows

So you want to know what the time is at GMT right now, or you need a fixed point to line other zones up against. That is what the clock at the top of this page is for. It shows the current time at Greenwich Mean Time and ticks forward every second, so there is nothing for you to work out by hand.

GMT sits at zero, neither ahead of nor behind Coordinated Universal Time. Wherever in the world you are reading this from, the clock holds steady at GMT, and unlike most local zones it does not shift back and forth with the seasons. You read it, you get on with your day.

Is GMT the same as UTC?

Here is the question almost everyone has about GMT, so let us deal with it first. Is GMT the same as UTC? For everyday purposes, yes. Both sit at zero offset, so a clock on GMT and a clock on UTC read the same time.

The difference is in what they are. GMT, Greenwich Mean Time, is the older one, worked out from the position of the sun over the Greenwich meridian in London. UTC, Coordinated Universal Time, is the modern standard, kept by a worldwide network of atomic clocks and nudged with the occasional leap second so it never drifts more than about a second from the sun. So in plain use the two are interchangeable. In precise, technical work, UTC is the one that is actually measured and distributed, and GMT is the name people have kept using out of habit and history. For the UTC side on its own page, see UTC Time Now.

What GMT actually is

GMT stands for Greenwich Mean Time. It is the mean solar time at the Royal Observatory in Greenwich, on the edge of London, and for a long stretch of history it was the clock the rest of the world set itself against. When you see a zone written as something like UTC plus 5 or UTC minus 8, the zero point those numbers count from is, in effect, Greenwich.

GMT is at zero offset, written UTC plus 0. It does not get ahead of or fall behind the global reference, it is the reference. That is why it turns up so often as the baseline in aviation, shipping, and anywhere people in different countries need one agreed clock to work from.

GMT and British Summer Time

One thing worth clearing up, because it catches people out. GMT is not the same as UK time all year. Britain runs on GMT through the winter, but in the summer it moves its clocks one hour forward to British Summer Time, or BST, at UTC plus 1. So from late March to late October, the United Kingdom is on BST and is one hour ahead of GMT, not on GMT at all.

This page stays on GMT itself, the fixed zero reference, which does not move. If it is current UK clock time you are after and the date falls in the summer, the clock you want is BST Time Now.

Converting GMT to other time zones

Because GMT sits at zero, it is the easiest possible thing to convert from: every other zone is just its own offset away. The catch is that many of those zones use daylight saving, so their gap to GMT shifts by an hour between summer and winter. The two below that do not use it, India and Japan, hold the same gap all year. Here is the quick reference. The right column assumes it is 12 noon GMT.

A few quick examples

Let us run a couple, so you can see how to use GMT as a reference.

Say it is 12 noon GMT. India does not change its clocks, so it is a steady 5 hours and 30 minutes ahead, which makes it 5:30 in the evening in Mumbai. Japan is 9 hours ahead, so 9 in the evening in Tokyo. Those two are easy, because neither uses daylight saving.

Now one that does. The US East Coast is 5 hours behind GMT in the winter, so noon GMT is 7 in the morning in New York. In the summer, when New York is on daylight saving, it is only 4 hours behind, so the same noon GMT becomes 8 in the morning there. The reference did not move, New York did, and that is the thing to watch whenever you line GMT up against a zone that springs forward.

Where GMT is used

As a clock that real places keep all year, GMT covers a handful of spots that sit at zero and do not use daylight saving. Iceland is the clearest example, staying on GMT the whole year round. Parts of West Africa do too, including Ghana and Senegal.

Then there are the places that are on GMT for only half the year. The United Kingdom, Ireland, and Portugal all keep GMT through the winter and move forward to summer time from late March to late October. So for those countries GMT is their winter clock, not their year-round one.

Beyond any single country, GMT, and its modern twin UTC, is used the world over as the baseline that every other time zone is measured from.

Cities on GMT

A couple of the cities on this site sit on GMT through the winter:

• London time now
• Edinburgh time now

Both of those move to British Summer Time from late March to late October, so they are on GMT only in the colder months. For the summer clock on its own page, see BST Time Now, and for the precise global standard that GMT is measured against, there is UTC Time Now.

Questions people ask

What time is it at GMT right now?

The clock near the top of this page is the answer, and it updates every second. GMT sits at zero offset and does not change for daylight saving, so it reads the same all year. It is the steady reference the other zones are measured against.

Is GMT the same as UTC?

For everyday use, yes. Both are at zero offset and read the same time. The difference is technical: GMT is the older timescale based on the sun over Greenwich, while UTC is the modern version kept by atomic clocks. If someone gives you a time in GMT, you can safely treat it as UTC.

What is the difference between GMT and UTC?

GMT is mean solar time at Greenwich, the historical world reference. UTC is the precise, atomic-clock standard that officially replaced it for technical timekeeping, held within about a second of GMT by leap seconds. In normal life they are interchangeable.

Does GMT change for daylight saving?

No. GMT itself is a fixed zero reference and never moves. What can confuse people is that the UK, which uses GMT in winter, springs forward to British Summer Time in summer. So the country changes, but GMT does not.

Is GMT the same as UK time?

Only in winter. The UK is on GMT from late October to late March, then moves one hour ahead to British Summer Time for the summer. So for roughly half the year, UK clock time is BST, one hour ahead of GMT.

How many hours ahead of UTC is GMT?

Zero. GMT and UTC are both at zero offset, so neither is ahead of the other. They show the same time.

References

1. Internet Assigned Numbers Authority (IANA). Time Zone Database (the tz database). https://www.iana.org/time-zones
2. International Bureau of Weights and Measures (BIPM), which maintains Coordinated Universal Time, the modern standard behind GMT. https://www.bipm.org/en/time-metrology
3. National Physical Laboratory (NPL), the United Kingdom's national timekeeper. https://www.npl.co.uk/
4. Royal Museums Greenwich, on the history and meaning of Greenwich Mean Time. https://www.rmg.co.uk/