Convert CET to GMT Central European Time ↔ Greenwich Mean Time Free Online Secure
Type a time in CET and read it in GMT straight away. The offset is −1 h, the arithmetic wraps at midnight, and the answer says which day it lands on.
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Through the day — Convert CET to GMT (Central European Time ↔ Greenwich Mean Time)
| CET | GMT |
|---|---|
| 00:00 | 23:00 |
| 03:00 | 02:00 |
| 06:00 | 05:00 |
| 09:00 | 08:00 |
| 12:00 | 11:00 |
| 15:00 | 14:00 |
| 18:00 | 17:00 |
| 21:00 | 20:00 |
Where these units come from
Until the middle of the nineteenth century every town kept its own noon, set by the sun overhead, and nobody minded that the next town was four minutes behind. Railways ended that: a timetable cannot be written for a hundred local noons. Britain put its railways on Greenwich time in 1847, and in 1884 the International Meridian Conference in Washington chose Greenwich as the prime meridian and sketched the twenty-four-hour scheme we still use. Greenwich Mean Time was the world's reference until 1972, when Coordinated Universal Time replaced it: UTC is kept by atomic clocks and tied back to the turning Earth by leap seconds. The abbreviations on this page name standard time — the winter setting — which is why each one is a fixed number of hours rather than something that drifts through the year.
Where you meet them
A time zone becomes real the moment two people in different places have to agree on one moment: a call between offices, a flight that lands before it took off, a market that opens while you are asleep, a deadline written in somebody else's afternoon. Server logs, train and flight schedules and anything stamped with a time are kept in UTC precisely so that the question can always be settled, no matter whose clock was on the wall.
Questions people ask
What about summer time?
The offsets here are standard-time offsets, the ones a zone keeps in winter. Where summer time is observed, the same places move one hour further on for part of the year and take a different name: Central European Time becomes Central European Summer Time, Eastern Standard Time becomes Eastern Daylight Time. The switching dates are not the same in every country, and the two hemispheres change in opposite months, so for a date inside a summer-time period add an hour to whichever side observes it.
Why isn't every difference a whole number of hours?
Because offsets are decided by governments, not by geometry. India is half an hour off the hour, at UTC+05:30; Nepal is three quarters, at UTC+05:45; the Chatham Islands are at UTC+12:45. Any of these can be changed by law, and several countries have moved their offset within living memory.
Is the answer exact?
Where both units are defined in terms of one another by whole numbers, yes — the page says so above the figure, and the only rounding is in how many digits are shown. Where the ratio has no finite decimal, the page shows twelve significant digits and says the relation is approximate rather than pretending otherwise.
Does anything I type leave my device?
No. The arithmetic runs in your browser; nothing is uploaded and there is no server to upload it to. Load the page once and it keeps working with the network switched off.
From the continent’s clock to London’s
You have a time written by someone in Frankfurt, Zurich, Milan, Madrid or Warsaw, and you want to know when it happens on a clock in Britain, Ireland or Portugal. All you need is a “convert CET to GMT” calculation, and it takes one subtraction: take away an hour. A trade-fair opening at 09:00 CET starts at 08:00 GMT, a train that leaves at 14:15 CET leaves at 13:15 GMT, and a deadline at 23:00 CET falls at 22:00 GMT. Only the first hour after midnight on the continental clock slips back across the date line of the day: 00:30 CET is 23:30 GMT on the previous date.
This page presents that rule, adds lookup tables, introduces the two zones, explains why the one-hour difference survives the clock changes, and then runs through trade fairs, carnival processions, football, rail, e-commerce deadlines and other situations in which a reader must make the conversion. Everything is calculated in your browser and nothing you enter leaves the page.
The subtraction behind a “convert CET to GMT” calculation
Take one hour away
CET is UTC+1 and GMT is UTC+0, so the continental clock leads the Greenwich clock by an hour. Subtract one from the CET hour each time you convert CET to GMT. If the result is negative, add 24 and step back a date. 00:45 CET gives −0:15, which is 23:45 GMT on the previous day.
Eight pairs of readings
00:30 CET is 23:30 GMT the day before. 06:15 CET is 05:15 GMT. 09:00 CET is 08:00 GMT. 12:00 CET is 11:00 GMT. 15:45 CET is 14:45 GMT. 18:00 CET is 17:00 GMT. 21:30 CET is 20:30 GMT. 23:45 CET is 22:45 GMT. One row changes the date, the other seven do not.
A habit that helps
London runs an hour behind the continent. When you hear “the shops close at six” in Paris, you know that the Londoner next to you will see the same moment on a clock that says five. The adjustment is small enough to do while walking.
Central European Time
Which countries use it
Central European Time covers the winter clocks of Germany, France, Italy, Spain, the Netherlands, Belgium, Luxembourg, Switzerland, Austria, Poland, Czechia, Slovakia, Hungary, Slovenia, Croatia, Serbia, Norway, Sweden and Denmark. It is also the clock of the European Union’s main institutions in Brussels and Strasbourg.
CET and CEST
CET belongs to the winter, from the last Sunday of October to the last Sunday of March. In summer these countries use Central European Summer Time, CEST, at UTC+2. The converter on this page is based on the winter value, UTC+1, but the answer you read is equally valid in summer when you compare CEST with BST.
Greenwich Mean Time as the target
Britain, Ireland, Portugal and Iceland
GMT is the winter time of the United Kingdom and Ireland. Mainland Portugal uses Western European Time, which equals GMT in winter. Iceland and several West African countries stay on GMT all year. Programmers also use the name for the zero-offset reference that coincides with UTC.
The wall clock in summer
From 29 March to 25 October 2026, the London wall clock shows BST. A British colleague who says “see you at 15:00 GMT” in July probably means 15:00 on the clock in London. Check the date before assuming that GMT is what the other person has in mind.
One hour and the working day
Seven hours in common
If the continental working day runs from 09:00 to 17:00 CET, the Greenwich clock reads 08:00 to 16:00. A London working day of 09:00 to 17:00 GMT reads 10:00 to 18:00 on the continent. The overlap is 09:00 to 16:00 GMT, or 10:00 to 17:00 CET: seven hours, enough for live meetings throughout the morning and early afternoon.
What the Londoner sees
A message sent from Milan at 17:00 CET reaches London at 16:00 GMT, when the office is still open. A message sent at 18:30 CET reaches London at 17:30 GMT, when it is not. The simplest rule for continental senders who convert CET to GMT in advance is to hit the button before 17:00 their time if they want an answer the same day.
By train to London
A Eurostar service that leaves Paris at 08:00 CET and takes about two hours and sixteen minutes reaches London at 09:16 GMT. The ticket shows 08:00 and 09:16, which suggests a trip of barely more than an hour, because the two stations are on different clocks.
The rule that keeps the gap constant
A shared legal framework
The European Union fixed a common calendar for summer time: it starts on the last Sunday of March and ends on the last Sunday of October, in each case at 01:00 UTC. Britain left the Union but kept the same dates. So when continental clocks jump forward, London’s do too, in the same instant.
What happens on the night
In the early hours of 29 March 2026, Paris moves from 02:00 to 03:00 and London from 01:00 to 02:00. On 25 October, Paris moves back from 03:00 to 02:00 and London from 02:00 to 01:00. Between those two nights, 14:00 CEST is 13:00 BST.
What the converter assumes
The page subtracts one hour, and that stays right all year if you are comparing the wall clocks of London and the continent. If your destination is pure UTC rather than London’s wall clock, subtract two hours from CEST in summer.
Trade fairs and exhibitions
Opening hours
Big fairs in Frankfurt, Hanover, Cologne and Munich typically open to visitors at 09:00 CET and close at 18:00 CET. In Greenwich time those hours are 08:00 and 17:00. An exhibitor who flies in from London on the first morning needs to convert CET to GMT for the first appointment, not only for the flight.
Seminars and press events
Press conferences often start at 10:30 CET, which is 09:30 GMT. Product launches take place at 11:00 CET, which is 10:00 GMT. British journalists who watch the stream from their desks should set the alarm for the earlier time.
Carnival in the Rhineland
The Monday procession
In Cologne, the Rose Monday procession, which in 2026 falls on 16 February, sets off in the morning, around 10:30 CET. That is 09:30 GMT. Broadcasters carry it live, and a viewer in London who wants the start must tune in an hour earlier on their own clock than the programme guide of the German channel indicates.
The rest of the programme
Evening events, such as masked balls, begin at 19:11 CET or 20:00 CET, which is 18:11 or 19:00 GMT. The symbolic hour of 11:11, observed at the start of the season, is 10:11 GMT.
Spanish and Italian football
Late kick-offs
Matches in Spain and Italy often start at 21:00 CET, which is 20:00 GMT. A fixture at 18:30 CET is at 17:30 GMT, and a lunchtime game at 12:30 CET is at 11:30 GMT. Fans in Britain who track several leagues should be ready to convert CET to GMT for each kick-off on a busy weekend.
Travelling to watch
A British supporter who flies from London to Madrid on a match day should note that a flight arriving at 17:00 GMT lands at 18:00 CET. With a kick-off at 21:00 CET the remaining time is three hours, which includes the metro and the security check.
Swiss railways and the clock
Punctual by design
Swiss trains are famously on time, and their timetables use CET in winter. A fast service leaving Zurich at 08:02 CET departs at 07:02 GMT. A connection in Bern at 09:36 CET is at 08:36 GMT. Visitors from Britain should set their watches to local time at the border.
Booking from abroad
Online tickets display the local time in a clear font, but confirmation e-mails sometimes use the time of the server. If the e-mail shows an hour that is one hour earlier than the ticket, the server was probably on Greenwich time.
E-commerce cut-offs
Order before two o’clock
Continental retailers often promise next-day delivery for orders placed before 14:00 CET. For a British customer that is 13:00 GMT. An order placed at 13:30 GMT is already past the limit, even though the customer’s clock shows lunchtime.
Returns and refunds
Return windows close at midnight local time. A deadline of 23:59 CET on a given date is 22:59 GMT on the same date. A customer in Britain who posts at 23:30 GMT misses it by half an hour, unless they remember to convert CET to GMT first.
Universities and online courses
Lectures from Zurich, Munich or Vienna
A live lecture that starts at 10:15 CET starts at 09:15 GMT. A seminar at 18:00 CET starts at 17:00 GMT. British students who join remotely should plan around the earlier hour on their own clocks.
Examination calendars
Exam timetables list start times in local time. A paper at 09:00 CET begins at 08:00 GMT. A student who is on an exchange programme and travels home on the same day should convert every time listed on the exam card.
Every hour in one table
CET to GMT
00:00 CET is 23:00 GMT (previous day). 01:00 CET is 00:00 GMT. 02:00 CET is 01:00 GMT. 03:00 CET is 02:00 GMT. 04:00 CET is 03:00 GMT. 05:00 CET is 04:00 GMT. 06:00 CET is 05:00 GMT. 07:00 CET is 06:00 GMT. 08:00 CET is 07:00 GMT. 09:00 CET is 08:00 GMT. 10:00 CET is 09:00 GMT. 11:00 CET is 10:00 GMT. 12:00 CET is 11:00 GMT. 13:00 CET is 12:00 GMT. 14:00 CET is 13:00 GMT. 15:00 CET is 14:00 GMT. 16:00 CET is 15:00 GMT. 17:00 CET is 16:00 GMT. 18:00 CET is 17:00 GMT. 19:00 CET is 18:00 GMT. 20:00 CET is 19:00 GMT. 21:00 CET is 20:00 GMT. 22:00 CET is 21:00 GMT. 23:00 CET is 22:00 GMT.
How to read the table
Each entry pairs one continental hour with its Greenwich hour and says when the date moves. The rows follow the single-hour subtraction that the calculator applies when you convert CET to GMT.
Ten readings with minutes
Examples
01:05 CET is 00:05 GMT. 03:20 CET is 02:20 GMT. 05:50 CET is 04:50 GMT. 07:35 CET is 06:35 GMT. 10:10 CET is 09:10 GMT. 13:25 CET is 12:25 GMT. 16:40 CET is 15:40 GMT. 19:55 CET is 18:55 GMT. 22:15 CET is 21:15 GMT. 23:05 CET is 22:05 GMT.
Minutes do not move
An hour is a whole unit, so the minutes in the answer match the minutes in the question.
What time of day is it in London?
Continental hours in the British day
06:00 CET is 05:00 GMT (early morning). 08:00 CET is 07:00 GMT (early morning). 10:00 CET is 09:00 GMT (morning). 12:00 CET is 11:00 GMT (morning). 14:00 CET is 13:00 GMT (around midday). 16:00 CET is 15:00 GMT (afternoon). 18:00 CET is 17:00 GMT (afternoon). 20:00 CET is 19:00 GMT (evening). 22:00 CET is 21:00 GMT (evening).
Using the list
The words in brackets describe the part of the day on the Greenwich clock. They show quickly whether a call is acceptable.
The European ladder
Starting from CET
Subtract one hour for London, Dublin and Lisbon in winter. Add one hour for Eastern Europe, including Bucharest, Athens and Helsinki, and two for Moscow. From Bucharest, subtract two hours to reach Greenwich, which is how you convert CET to GMT for a Romanian reader.
One instant on four clocks
When it is 14:00 in Paris, it is 13:00 in London, 15:00 in Bucharest and 16:00 in Moscow. Listing the four in an invitation saves every reader from having to convert CET to GMT separately.
Dated examples through the year
Mid-January
On Thursday 15 January, 14:00 CET is 13:00 GMT, because both zones are on winter time.
Late March
On Thursday 26 March, 14:00 CET is still 13:00 GMT. The change does not take place until 29 March.
Mid-July
On Thursday 16 July, 14:00 CEST is 13:00 BST, and the difference is still one hour.
November
On Thursday 12 November, 14:00 CET is 13:00 GMT. Both zones have been back on winter time since 25 October.
Checklist: how to convert CET to GMT
Before
Read the labels
CET is winter and CEST is summer. A source that says only “Central European Time” leaves the gap to London at one hour either way.
Decide the target
For London’s wall clock, subtract one hour all year. For pure UTC, subtract two hours from CEST in summer.
After
Subtract one
If the result is below zero, add 24 and use the previous date.
Check the date
Only readings between 00:00 and 00:59 CET move to the previous date.
Evening news and public broadcasting
The main bulletin
The principal evening news on German public television goes out at 20:00 CET, which is 19:00 GMT. French television news is broadcast at 20:00 CET, too. A British viewer who follows continental headlines through a web stream therefore sees the lead story an hour before the clock in the programme guide suggests.
Radio programmes
A morning programme that starts at 06:00 CET starts at 05:00 GMT, before dawn in Britain in winter. Podcasts published at 07:00 CET appear at 06:00 GMT. To plan a day around continental media, do the “convert CET to GMT” calculation once per programme and write the answer next to the original in your diary.
Laboratories and pharmaceutical shifts
Basel, Frankfurt and Milan
Pharmaceutical plants in Switzerland, Germany and Italy run on three shifts, usually starting at 06:00, 14:00 and 22:00 CET. In Greenwich time the shifts start at 05:00, 13:00 and 21:00. A British partner that needs lab results by a particular hour should specify the clock, because a result promised for “the end of the morning shift” means 14:00 CET, or 13:00 GMT.
Quality records
Batch records carry time stamps in the local clock of the plant. If an auditor in London compares them with records of a British site, each entry must be moved by one hour. The simplest solution is to store everything in UTC and show CET only on screen.
Skiing home from the Alps
Last lift, last flight
Lifts in the Alps close at about 16:30 CET, which is 15:30 GMT. A flight from Geneva at 19:45 CET leaves at 18:45 GMT and lands in London at about 20:35 GMT. A skier who skis until the last lift has three hours to reach the airport, return the equipment and clear security.
Transfers on the way
Transfers are booked in local time. A coach at 15:00 CET leaves at 14:00 GMT, which is easy to forget after a week on holiday when the watch was set to local time. If you need a “convert CET to GMT” calculation for the return trip, do it the evening before.
Mistakes when you convert CET to GMT
Adding an hour
London is behind the continent. If your answer is later than the CET time, you added.
Mixing up Romanian time
Romania is one hour ahead of CET. From a Bucharest clock, subtract two hours to reach GMT.
Forgetting the early-morning rule
00:20 CET is still the previous evening in London: 23:20 GMT.
Using the winter figure for UTC in summer
In summer CEST is two hours ahead of true UTC, so subtracting one hour gives the London wall clock, not the zero meridian.
Frequently asked questions
How far apart are CET and GMT?
One hour, with CET ahead.
What is the formula to convert CET to GMT?
CET hour minus one, adding 24 if the result is negative.
What is 14:00 CET in GMT?
13:00 GMT.
Does the gap change in summer?
Not if you compare wall clocks. London and the continent change on the same night, so it remains one hour.
Does the page keep my input?
No. It stays in your browser.
More time zone converters
You might also want Convert CET to EET, Convert CET to CST, Convert IST to GMT, Convert WET to GMT, Convert GMT to EET, Convert WET to CET, Convert CET to EST, Convert IST to EET, Convert PST to EST. To go the other way, use Convert GMT to CET.
In brief, to convert CET to GMT you subtract one hour, watch the first hour after midnight and keep the Romanian clock separate from CET. The calculation runs on your own device, with no account and no upload.