Convert CET to IST Central European Time ↔ India Standard Time Free Online Secure
Type a time in CET and read it in IST straight away. The offset is +4:30 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 IST (Central European Time ↔ India Standard Time)
| CET | IST |
|---|---|
| 00:00 | 04:30 |
| 03:00 | 07:30 |
| 06:00 | 10:30 |
| 09:00 | 13:30 |
| 12:00 | 16:30 |
| 15:00 | 19:30 |
| 18:00 | 22:30 |
| 21:00 | 01:30 |
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.
The Hanover fair, German football and the clock in Pune
The industrial fair in Hanover opens at 09:00. A match in the German league kicks off on Saturday at 15:30. The European Central Bank announces its decision at 14:15. A reader in Mumbai, Pune or Delhi has to convert CET to IST, and on standard time the rule is a single line: add four and a half hours. 09:00 CET becomes 13:30 IST, 15:30 CET becomes 20:00 IST, and 14:15 CET becomes 18:45 IST. India does not move its clocks, so the result changes only when Europe goes onto summer time: from 29 March to 24 October the difference is three and a half hours.
The page covers the rule, the tables, a description of the zones and episodes from trade, sport, aviation, finance and remote work. The calculation takes place in your browser, and no figure is sent to a server.
The industrial fair in Hanover
Indian exhibitors
The fair’s gates open in the morning, at 09:00 CEST, which is 12:30 IST. Indian stands send messages home at the start of the afternoon, when offices in India are in full swing.
Evening presentations
A presentation at 17:00 CEST is at 20:30 IST. A “convert CET to IST” calculation shows at once whether it falls before or after the Indian dinner hour.
German football followed from India
The Saturday match
A match that kicks off at 15:30 CET kicks off at 20:00 IST. Indian fans follow it in the evening, after work, and it ends toward 22:00.
The summer match
In the warm season, a match at 15:30 CEST is at 19:00 IST. The four-and-a-half-hour figure falls to three and a half, because India does not change its clocks.
The European Central Bank’s decision
The afternoon announcement
The interest-rate decision appears at 14:15 CET, which is 18:45 IST. The press conference starts at 14:45 CET, which is 19:15 IST. Indian traders follow it live at the end of their day.
The effect on the rupee
The rupee reacts within seconds, but the Mumbai exchange is already closed, since it ends at 15:30 IST. A “convert CET to IST” calculation shows that the reaction appears only the next morning.
Flights between Frankfurt and Delhi
The afternoon departure
A flight from Frankfurt to Delhi that leaves at 13:00 CET and takes nearly nine hours lands at 21:50 CET, which is 02:20 IST the next day. The ticket shows 13:00 and 02:20, as for a flight of thirteen hours, although it lasts nine.
The return
A flight from Delhi that leaves at 03:00 IST and takes nearly nine hours lands at 12:00 IST, which is 07:30 CET. A “convert CET to IST” calculation tells you at once whether you will make the first meeting.
Indian films at the foot of the Alps
Filming in Switzerland
Crews filming in Switzerland start work at 08:00 CET, which is 12:30 IST. Producers in Mumbai follow the shoot live during the afternoon.
European premieres
A gala premiere at 19:00 CET is at 23:30 IST. Indian film fans watch it late in the evening.
Indian students in Germany
Morning classes
A class at 10:00 CET is at 14:30 IST. Families in India follow the lecture streamed online in the first part of the afternoon.
Submission deadlines
A deadline for filing an application “by 17:00” German time is at 21:30 IST. A “convert CET to IST” calculation shows that the German day ends, in India, at dinner time.
The travel fair in Berlin
The first day
The fair opens at 10:00 CET, which is 14:30 IST. Indian agencies catch the morning presentations in the first part of the afternoon.
The speeches
The official speech at 11:30 CET is at 16:00 IST. Whoever does a “convert CET to IST” calculation knows it falls just after the tea break.
How to convert CET to IST, stage by stage
Stage one: the addition
CET is UTC+1 and India sits at UTC+5:30. Four hours 30 minutes separate the two, with India ahead. Write the European time on a 24-hour clock and add 4:30.
Stage two: the date
If the total passes 24:00, subtract 24 and go to the next day. That happens for every European time from 19:30 onward.
Stage three: the check
02:00 CET is 06:30 IST. 05:15 CET is 09:45 IST. 08:30 CET is 13:00 IST. 11:00 CET is 15:30 IST. 14:45 CET is 19:15 IST. 18:30 CET is 23:00 IST. 20:00 CET is 00:30 IST the next day. 23:15 CET is 03:45 IST the next day. The last two roll over to the next day.
Central European time
Who uses it
Germany, France, Italy, mainland Spain, Poland, Austria, Switzerland, Hungary, Sweden and Norway run on CET (UTC+1) in winter. In summer they move to CEST (UTC+2), from the last Sunday of March to the last Sunday of October.
Romania
A reader in Bucharest adds three and a half hours, not four and a half, because Romania is an hour ahead of Central Europe.
Indian time
One clock
From Gujarat to Assam India uses UTC+5:30, with no move to summer time. The half hour changes the minutes of the result: 09:15 CET becomes 13:45 IST.
The neighbours
Sri Lanka keeps the same time as India. Nepal is on UTC+5:45, Pakistan on UTC+5, Bangladesh on UTC+6.
Four and a half hours on the dial
Office hours
A European office open from 09:00 to 17:00 works, on Indian time, from 13:30 to 21:30. An Indian office open from 09:00 to 17:00 works from 04:30 to 12:30 on Central European time. The two days overlap for three and a half hours, from 13:30 to 17:00 IST, which is 09:00 to 12:30 CET.
Who rings first
A call from Germany at 09:00 CET rings at 13:30 IST, in the first part of the Indian afternoon. One from 16:00 CET rings at 20:30 IST, as the Indian colleagues head home.
The direct flight
A flight from Munich to Mumbai that leaves at 14:00 CET and takes nearly eight and a half hours lands at 22:30 CET, which is 03:00 IST the next day. The ticket shows 14:00 and 03:00, as for a trip of thirteen hours.
Outsourcing: offices in India for European clients
The sync hour
Teams in India working for clients in Germany meet them at 14:30 IST, which is 10:00 CET. The shared window runs from 13:30 to 17:00 IST.
What stays in writing
Work that ends at 17:30 IST reaches the European clients at 13:00 CET, in the middle of their working day. A written handover keeps the thread.
Dated examples
January
On Wednesday 14 January, 15:00 CET is 19:30 IST. The gap is four and a half hours.
The end of March
On Wednesday 25 March, 15:00 CET is still 19:30 IST. On Wednesday 1 April, 15:00 CEST is 18:30 IST: Europe went onto summer time on 29 March, India did not, so the difference fell to three and a half hours.
Summer
On Wednesday 22 July, 15:00 CEST is 18:30 IST. The gap is three and a half hours.
Autumn
On Wednesday 28 October, 15:00 CET is 19:30 IST, after Europe’s return to standard time on 25 October. On Wednesday 9 December, 15:00 CET is 19:30 IST.
Why it is sometimes three and a half hours
From March to October
From 29 March to 24 October, Central Europe is on summer time and India is not. The distance then shrinks by an hour.
How to correct
A “convert CET to IST” calculation made with the winter figure gives, in the warm season, a result an hour too late. The correction is always the same: subtract an hour.
More Asian clocks, counted from Central Europe
How many hours to add
From Central European time add four and a half hours for India, four and three-quarters for Nepal, seven for China and Singapore and eight for Japan. In summer, subtract an hour from each.
One instant on four clocks
When it is 12:00 in Berlin in winter, it is 16:30 in Delhi, 17:00 in Dhaka, 19:00 in Singapore and 20:00 in Tokyo. Whoever writes all the hours in the invitation spares the guests a “convert CET to IST” calculation.
Online courses from German universities
Course time
A lesson at 09:00 CET is at 13:30 IST. Students in India follow it in the first part of the afternoon.
Deadlines
A deadline of 23:59 CET is at 04:29 IST the next day. An Indian student who counts the deadline as midnight on their own clock actually has half a night more.
Telemedicine between Germany and India
Appointments
A consultation scheduled for 10:00 CET is at 14:30 IST. Indian doctors receive German patients in the first part of their afternoon.
Prescriptions and dates
A prescription issued at 01:00 IST on 5 March was issued at 20:30 CET on 4 March. A “convert CET to IST” calculation made with the date in view shows the exact day of issue.
Alpine weather, followed from India
Warnings
A warning valid until 18:00 CET expires at 22:30 IST. Families in India following the situation of relatives in the Alps add four and a half hours to every hour in the bulletin.
How to read it
Each bulletin carries the local time of Central Europe. A “convert CET to IST” calculation for both times shows when the latest version appeared.
The weeks and months that need care
The 2026 calendar
The gap between CET and IST changes during the year. In 2026: 1 January to 28 March and 25 October to 31 December: IST is 4 hours 30 minutes ahead of CET; 29 March to 24 October: IST is 3 hours 30 minutes ahead of CET.
How to apply it
During the summer periods the zones are called CEST and IST. The calculator assumes the winter gap of 4 hours 30 minutes; adjust by the difference shown for your date. Before you convert CET to IST, find the period that contains your date.
All twenty-four hours side by side
CET against IST
00:00 CET = 04:30 IST. 01:00 CET = 05:30 IST. 02:00 CET = 06:30 IST. 03:00 CET = 07:30 IST. 04:00 CET = 08:30 IST. 05:00 CET = 09:30 IST. 06:00 CET = 10:30 IST. 07:00 CET = 11:30 IST. 08:00 CET = 12:30 IST. 09:00 CET = 13:30 IST. 10:00 CET = 14:30 IST. 11:00 CET = 15:30 IST. 12:00 CET = 16:30 IST. 13:00 CET = 17:30 IST. 14:00 CET = 18:30 IST. 15:00 CET = 19:30 IST. 16:00 CET = 20:30 IST. 17:00 CET = 21:30 IST. 18:00 CET = 22:30 IST. 19:00 CET = 23:30 IST. 20:00 CET = 00:30 IST (next day). 21:00 CET = 01:30 IST (next day). 22:00 CET = 02:30 IST (next day). 23:00 CET = 03:30 IST (next day).
Notes on the table
The table lists the full day. Where the IST date differs from the CET date, the entry says so. Use it as a reference whenever you convert CET to IST. This pair has a half-hour in its offset, so every :00 becomes :30, every :15 becomes :45 and so on, with the hour carried over. These rows use the standard (winter) gap; on the dates listed in the period section the gap is different.
Half-hour conversions
CET half-hours in IST
00:30 CET = 05:00 IST. 01:30 CET = 06:00 IST. 02:30 CET = 07:00 IST. 03:30 CET = 08:00 IST. 04:30 CET = 09:00 IST. 05:30 CET = 10:00 IST. 06:30 CET = 11:00 IST. 07:30 CET = 12:00 IST. 08:30 CET = 13:00 IST. 09:30 CET = 14:00 IST. 10:30 CET = 15:00 IST. 11:30 CET = 16:00 IST. 12:30 CET = 17:00 IST. 13:30 CET = 18:00 IST. 14:30 CET = 19:00 IST. 15:30 CET = 20:00 IST. 16:30 CET = 21:00 IST. 17:30 CET = 22:00 IST. 18:30 CET = 23:00 IST. 19:30 CET = 00:00 IST (next day). 20:30 CET = 01:00 IST (next day). 21:30 CET = 02:00 IST (next day). 22:30 CET = 03:00 IST (next day). 23:30 CET = 04:00 IST (next day).
What to remember
Half-hour starts are as easy to convert as whole hours. The rows below are the result of the same rule you use when you convert CET to IST. Read these rows as standard-time values and check the period section for dates where the difference changes.
Conversions with minutes
CET into IST
01:05 CET = 05:35 IST. 03:20 CET = 07:50 IST. 05:50 CET = 10:20 IST. 07:35 CET = 12:05 IST. 10:10 CET = 14:40 IST. 13:25 CET = 17:55 IST. 16:40 CET = 21:10 IST. 19:55 CET = 00:25 IST (next day). 22:15 CET = 02:45 IST (next day). 23:05 CET = 03:35 IST (next day).
How to check
Each line shows how a time with minutes is carried across. The half-hour in the offset moves each minute reading by thirty, which is why this pair needs a second look. Read these rows as standard-time values and check the period section for dates where the difference changes.
Daily rhythm at the other end
IST time of day for chosen CET hours
06:00 CET = 10:30 IST (morning). 08:00 CET = 12:30 IST (around midday). 10:00 CET = 14:30 IST (afternoon). 12:00 CET = 16:30 IST (afternoon). 14:00 CET = 18:30 IST (evening). 16:00 CET = 20:30 IST (evening). 18:00 CET = 22:30 IST (night). 20:00 CET = 00:30 IST (night). 22:00 CET = 02:30 IST (night).
Using the brackets
The brackets show whether the IST hour falls at night, in the early morning, during the working day or in the evening, which helps when you must convert CET to IST for a call. These rows use the standard (winter) gap; on the dates listed in the period section the gap is different.
Checklist: how to convert CET to IST
Preparation
Confirm the zones
Do not use CET for Romania, Bulgaria or Greece; they are on Eastern European Time, an hour ahead. If a schedule says IST, make sure it comes from India: Israel and Ireland use those letters too, at other offsets.
Use a 24-hour clock
The 24-hour clock avoids a.m. and p.m. slips, so rewrite 4:30 p.m. as 16:30 before anything else. For example, 09:15 CET becomes 13:45 IST.
After the sum
The operation
Add 4 hours 30 minutes. If the result passes midnight, correct the date: readings from 19:30 fall on the next date.
A second example
Late in the evening, 22:40 CET becomes 03:10 IST (next day).
Traps to avoid when you convert CET to IST
Subtracting instead of adding
Because IST runs ahead of CET, the result must be a later clock reading. An earlier one points to a subtraction.
Losing the date
A CET time from 19:30 moves to the next date. Forgetting to move the date leaves the result 24 hours wrong.
The standard figure in the wrong weeks
On some dates in 2026 the distance between CET and IST differs from the usual one, so read the period list before you apply it.
Confusing the abbreviation
Romania is not on CET: it uses Eastern European Time, one hour ahead. The letters IST are shared with Ireland’s summer clock and Israel’s standard time; this page means India.
Questions and answers
How far apart are CET and IST?
4 hours 30 minutes, and IST is ahead of CET. That is the standard figure; on some dates in 2026 it differs, as the period list shows.
How do I convert CET to IST?
Add 4 hours 30 minutes to the CET time, then fix the date if the result passes midnight.
How much is 21:45 CET in IST?
02:15 IST on the next day in the standard period.
Is the gap the same in every month?
No, it differs on some dates; the period list above shows which.
Does the page keep what I type?
No. Everything happens on your own device.
Where to go next
You may also want Convert CET to EET, Convert CET to CST, Convert GMT to IST, Convert UTC to IST, Convert IST to GMT, Convert PST to CET, Convert PST to IST, Convert WET to IST, Convert GMT to PST. To go the other way, use Convert IST to CET.
The short version: add 4 hours 30 minutes, check the date, and you can convert CET to IST with confidence. No account is needed.