Convert GMT to CET Greenwich Mean Time ↔ Central European Time Free Online Secure
Type a time in GMT and read it in CET 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 GMT to CET (Greenwich Mean Time ↔ Central European Time)
| GMT | CET |
|---|---|
| 00:00 | 01:00 |
| 03:00 | 04:00 |
| 06:00 | 07:00 |
| 09:00 | 10:00 |
| 12:00 | 13:00 |
| 15:00 | 16:00 |
| 18:00 | 19:00 |
| 21:00 | 22:00 |
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.
One hour east of London
Continental Europe sits just across the Channel, yet its clocks are not in step with Britain’s. Paris, Berlin, Rome, Madrid, Amsterdam, Brussels, Vienna, Prague, Warsaw and Stockholm all run on Central European Time. If a time was written in Greenwich Mean Time and you want to know what it shows in those cities, you need to convert GMT to CET. The rule is as light as a conversion can be: add one hour. 08:30 GMT is 09:30 CET, 15:00 GMT is 16:00 CET, and 23:45 GMT is 00:45 CET on the following date.
Better still, the gap does not change with the seasons. Britain and the continent move their clocks on the same night, so the lead of one hour holds in summer as well as winter. The page explains the rule, supplies lookup tables, introduces both zones, and goes through practical cases from trains and ferries to bank payments and ski lifts. Everything is computed in your browser, and nothing you enter is sent to a server.
How to convert GMT to CET
Add one hour
CET is UTC+1 and GMT is UTC+0. Add one to the hour on the Greenwich clock. If the sum is 24 or more, subtract 24 and advance the date. Only readings from 23:00 GMT onward cross midnight: 23:10 GMT is 00:10 CET the next day.
Eight readings
00:30 GMT is 01:30 CET. 06:15 GMT is 07:15 CET. 09:00 GMT is 10:00 CET. 12:00 GMT is 13:00 CET. 15:45 GMT is 16:45 CET. 18:00 GMT is 19:00 CET. 21:30 GMT is 22:30 CET. 23:45 GMT is 00:45 CET the following day.
A thought experiment
Imagine you are at your desk in London and a colleague in Paris says it is lunchtime. At 12:00 in London the Parisian is already finishing at 13:00. When the London office closes at 17:00 the Paris office closes an hour later by the clock on its own wall. The extra hour is always on the continental side.
Greenwich Mean Time in this pairing
Winter in Britain
GMT is the standard time of Britain and Ireland from the last Sunday of October to the last Sunday of March. During the other months the British clock reads BST, one hour ahead, and the continent moves one hour ahead in the same hour of the same night. That symmetry is the reason the gap stays at one hour.
GMT as a label for UTC
On computers, GMT also names the zero-offset reference that coincides with UTC. A log line stamped GMT in July therefore means the true zero meridian clock, not the British wall clock. In that case, the continental local time is two hours later in summer, not one, and you must use CEST rather than CET.
Central European Time
The countries concerned
CET is the legal winter time of Germany, France, Italy, Spain, Poland, the Netherlands, Belgium, Luxembourg, Switzerland, Austria, the Czech Republic, Slovakia, Hungary, Slovenia, Croatia, Serbia, Norway, Sweden and Denmark. In the summer these countries change to Central European Summer Time, CEST, at UTC+2.
Where Romania fits
Romania, Bulgaria, Greece and Finland use Eastern European Time, one hour ahead of CET. If a business partner in Berlin proposes 10:00 CET, the same moment is 11:00 in Bucharest and 09:00 in London.
How one hour reshapes the working day
A very long overlap
An office in London open from 09:00 to 17:00 GMT is open from 10:00 to 18:00 CET. An office in Berlin open from 09:00 to 17:00 CET is open from 08:00 to 16:00 GMT. The two days overlap from 09:00 to 16:00 GMT, seven hours of shared working time. No other pair of major zones comes close for convenience.
Lunchtimes drift apart
Continental lunch breaks around 12:30 to 13:30 CET fall between 11:30 and 12:30 GMT, while Londoners go out between 12:30 and 13:30. A call set at 12:00 GMT interrupts lunch in Paris. Calls at 10:30 or 14:30 GMT avoid it for both sides.
By train under the sea
A train that leaves London at 09:00 and runs to Paris in about two hours and sixteen minutes arrives at 11:16 GMT, which a station clock in Paris shows as 12:16. On the ticket, the arrival time is printed in French time, so the journey looks three hours long, not two and a quarter.
Why there are no mismatched weeks
One rule for both sides
European summer time begins on the last Sunday of March and ends on the last Sunday of October, at 01:00 UTC in each case. Britain retained the same dates after leaving the European Union. As a result London and the continent change their clocks at the same instant, and no stretch of the calendar has them out of line.
The 2026 transitions
On 29 March 2026 London moves from GMT to BST and Central Europe from CET to CEST, both at 01:00 UTC. On 25 October 2026 both move back. During summer 10:00 BST is 11:00 CEST, and the gap is still one hour.
What it means for you
The answer to a request to convert GMT to CET is the same in every month. The only trap lies in labels: a Londoner who writes “GMT” in July is usually referring to the wall clock, which is BST.
Flying between Britain and the continent
Short flights, double clocks
A flight from London to Frankfurt that leaves at 10:00 GMT and lasts about one hour forty minutes lands at 11:40 GMT, which is 12:40 CET. The boarding pass shows the departure in British time and the arrival in German time, so the trip appears to last two hours forty minutes. Only the passenger who runs a “convert GMT to CET” calculation sees the real duration.
Return journeys
A flight back from Frankfurt at 18:00 CET lands about an hour and forty minutes later at 18:40 GMT, because 18:00 CET is 17:00 GMT. The return journey looks two hours shorter than the outward one on the printed times, which is a handy check on your arithmetic.
Bank payments inside the euro area
Operating hours of the payment system
The large-value payment system of the Eurosystem operates from 07:00 to 18:00 CET on business days. In Greenwich time those hours are 06:00 to 17:00. A British company that needs a euro transfer to settle the same day should send it before 16:00 GMT to leave a margin.
Reading the cut-off
Banks print cut-off times in local time, and the local time may be that of the head office rather than the branch you use. After you convert GMT to CET, check that the result is before the end of your own working day.
Opera, theatre and concerts
Curtain times
An evening performance in Vienna or Berlin typically starts at 19:30 CET, which is 18:30 GMT. A matinee at 15:00 CET starts at 14:00 GMT. Visitors who fly in from Britain for the day should plan the return flight with the later clock in mind.
Live broadcasts
Operas broadcast live to cinemas begin at 19:00 CET, which is 18:00 GMT, so a British audience sees them an hour earlier on its own clock. Interval talks are timed in the broadcaster’s local time.
Motor racing and winter sports
Grand Prix starts
European Grands Prix of Formula One usually start at 15:00 local time. In summer that is 15:00 CEST, or 14:00 BST. The same 15:00 on a CET clock would be 14:00 GMT. Either way, the British viewer sees the lights go out an hour earlier on the wall clock.
Ski races
World Cup downhill races in the Alps normally start at 11:30 CET, which is 10:30 GMT. British viewers who set an alarm to watch from the first gate should convert GMT to CET for each run to see the real start of the broadcast.
Remote work with Berlin and Warsaw
A friendly overlap
A start-up in Berlin, a design team in Warsaw and a sales team in London can hold their stand-up at 09:30 GMT, which is 10:30 CET. The team in London has had a quiet hour, and the teams on the continent have not yet had lunch.
Documenting the hour
Write the time with both zones, as in “09:30 GMT / 10:30 CET”. In summer the labels change to BST and CEST, but the numbers remain the same, because the gap is fixed at one hour.
Radio-controlled clocks
The German time signal
The long-wave time signal transmitted near Frankfurt carries the legal time of Germany: CET in winter and CEST in summer. A radio-controlled clock that receives it displays the correct continental time. Taken to Britain, it will show one hour more than the British clock in winter and still one hour more in summer.
Setting a clock correctly
If you want your own wall clock on Greenwich time, subtract one hour from the reading you get from a German-controlled clock. It is the mirror image of the rule you use when you convert GMT to CET.
Every hour in one table
GMT to CET
00:00 GMT = 01:00 CET. 01:00 GMT = 02:00 CET. 02:00 GMT = 03:00 CET. 03:00 GMT = 04:00 CET. 04:00 GMT = 05:00 CET. 05:00 GMT = 06:00 CET. 06:00 GMT = 07:00 CET. 07:00 GMT = 08:00 CET. 08:00 GMT = 09:00 CET. 09:00 GMT = 10:00 CET. 10:00 GMT = 11:00 CET. 11:00 GMT = 12:00 CET. 12:00 GMT = 13:00 CET. 13:00 GMT = 14:00 CET. 14:00 GMT = 15:00 CET. 15:00 GMT = 16:00 CET. 16:00 GMT = 17:00 CET. 17:00 GMT = 18:00 CET. 18:00 GMT = 19:00 CET. 19:00 GMT = 20:00 CET. 20:00 GMT = 21:00 CET. 21:00 GMT = 22:00 CET. 22:00 GMT = 23:00 CET. 23:00 GMT = 00:00 CET (next day).
How to read it
Each entry pairs one Greenwich hour with the matching continental hour and notes when the date moves. The rows follow the single-hour addition that the calculator uses when you convert GMT to CET.
Ten readings with minutes
Examples
01:05 GMT = 02:05 CET. 03:20 GMT = 04:20 CET. 05:50 GMT = 06:50 CET. 07:35 GMT = 08:35 CET. 10:10 GMT = 11:10 CET. 13:25 GMT = 14:25 CET. 16:40 GMT = 17:40 CET. 19:55 GMT = 20:55 CET. 22:15 GMT = 23:15 CET. 23:05 GMT = 00:05 CET (next day).
The minutes stay the same
Because the difference is a whole hour, the minutes in the answer match those in the question.
What part of the day is it?
The continental view of each GMT hour
06:00 GMT = 07:00 CET (early morning). 08:00 GMT = 09:00 CET (morning). 10:00 GMT = 11:00 CET (morning). 12:00 GMT = 13:00 CET (around midday). 14:00 GMT = 15:00 CET (afternoon). 16:00 GMT = 17:00 CET (afternoon). 18:00 GMT = 19:00 CET (evening). 20:00 GMT = 21:00 CET (evening). 22:00 GMT = 23:00 CET (night).
How to use the list
The words in brackets describe the part of the day on the continent. They help you avoid planning a call for the middle of the night.
European zones seen from Greenwich
The ladder
Add zero for London, Dublin and Lisbon in winter, one hour for Central Europe, two for Eastern Europe, three for Moscow and Istanbul, and five and a half for India. If someone says “Central European”, add one, not two.
One moment, four clocks
When London reads 10:00, Paris reads 11:00, Bucharest 12:00 and Moscow 13:00. Listing these four times in an invitation saves everyone from having to convert GMT to CET again.
Dated examples
January
On Wednesday 14 January, 15:00 GMT is 16:00 CET. Both sides are on winter time.
Late March
On Wednesday 25 March, 15:00 GMT is 16:00 CET. The clocks do not change until 29 March, so nothing is different.
July
On Wednesday 15 July, 15:00 BST is 16:00 CEST. Both sides are on summer time and the gap is still one hour.
November
On Wednesday 11 November, 15:00 GMT is 16:00 CET. Both have been back on winter time since 25 October.
Checklist: how to convert GMT to CET
Before
Read the label
CET is winter, CEST is summer. If the source only says “Central European”, the gap to London is one hour in either case.
Check the British side
A Londoner’s “GMT” in July usually means BST.
After
Add one hour
If the sum is 24 or more, subtract 24 and advance the date.
Check the date
Only GMT hours from 23:00 onward move to the next date.
City breaks and hotel check-ins
A weekend in Amsterdam, Prague or Rome
Hotels publish check-in times in local time. A check-in from 15:00 CET is available from 14:00 GMT, which may be earlier than you expect if your flight lands at 13:30 GMT. Checkout at 11:00 CET is 10:00 GMT. A traveller who wants to convert GMT to CET for each booking confirmation will not be caught out.
Tours and tickets
Guided tours start at the time printed on the voucher, in local time. A museum slot at 10:30 CET is 09:30 GMT, and the last entry at 17:00 CET is 16:00 GMT. If your phone is still on British time at the airport, you will find yourself an hour early.
Lorries and the Channel Tunnel
Timetables on both sides
Freight operators that cross the Channel by train or ferry publish slots in the local time of the terminal. A departure from Folkestone at 14:00 GMT arrives at Calais, after a crossing of roughly thirty-five minutes, at 14:35 GMT, which is 15:35 CET. Drivers set their tachographs to a single reference and use a “convert GMT to CET” calculation to translate the local slot on paperwork.
Customs windows
Customs offices on the continent close according to their own clocks. A cut-off at 17:00 CET is 16:00 GMT, and a consignment that arrives at 16:30 GMT is already one hour late for the office, even though the clock on the lorry says half past four.
Song contests and televised finals
Prime time on the continent
A large European television final scheduled for 21:00 CET is shown at 20:00 GMT. In summer, when the same final is announced for 21:00 CEST, the British transmission is at 20:00 BST. Viewers in Britain therefore enjoy the same one-hour head start all year.
Voting windows
Voting often opens at the start of the final and closes shortly after the last performance, around 23:45 CET, which is 22:45 GMT. If you plan to vote from London, do a quick convert GMT to CET on the closing time rather than relying on the host’s clock.
Mistakes when you convert GMT to CET
Subtracting an hour
The continent is ahead of London. If your answer is earlier than the input, you subtracted.
Confusing CET with Romanian time
Romania is on Eastern European Time, which is one hour ahead of CET. For Bucharest, add two hours to GMT.
Adding two hours in summer
In summer, BST to CEST is still one hour. Add two only if the source is the zero-offset scale.
Losing the date
23:30 GMT is 00:30 CET the next day. Do not carry the original date over.
Frequently asked questions
What is the difference between GMT and CET?
One hour. CET is ahead of GMT.
How do I convert GMT to CET?
Add one hour, subtracting 24 and moving to the next date if the sum is 24 or more.
What is 12:00 GMT in CET?
13:00 CET.
Does the gap change in summer?
No. London and Central Europe change their clocks together, so the gap remains one hour.
Is my input saved anywhere?
No. It stays in your browser.
More time zone converters
You might also want Convert GMT to CST, Convert GMT to IST, Convert EET to CET, Convert UTC to CET, Convert CET to IST, Convert EST to GMT, Convert UTC to WET, Convert EST to EET, Convert EST to CST. For the reverse direction, use Convert CET to GMT.
In brief, to convert GMT to CET you add one hour, watch for the midnight crossing and keep CET apart from the time in Romania. The calculation runs on your own device, with no sign-up and no upload.