Convert IST to CET India Standard Time ↔ Central European Time Free Online Secure
Type a time in IST and read it in CET 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 IST to CET (India Standard Time ↔ Central European Time)
| IST | CET |
|---|---|
| 00:00 | 19:30 |
| 03:00 | 22:30 |
| 06:00 | 01:30 |
| 09:00 | 04:30 |
| 12:00 | 07:30 |
| 15:00 | 10:30 |
| 18:00 | 13:30 |
| 21:00 | 16:30 |
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 Bangalore tech summit, read in Zurich
The technology summit in Bangalore opens its doors at 10:00 IST. A match at the field hockey World Cup starts that evening at 19:00. The Air Force Day flypast in India takes off at 10:00 in the morning. Someone in Zurich, Berlin, Vienna or Paris who wants those moments on the clock at home will convert IST to CET. In the dark half of the year the sum is a subtraction of four and a half hours: 10:00 IST reads 05:30 CET, 19:00 IST reads 14:30 CET, and 02:00 IST falls back to the evening before as 21:30 CET. Indian clocks never move, so only a change in Europe alters the answer: between 29 March and 24 October you take away three and a half hours instead.
First come Indian events followed from Central Europe, then the rule, the lookup tables and a portrait of each zone. Every calculation happens in your browser and no figure is sent to a server.
The tech summit in Bangalore
Opening speeches
The first session in November begins at 10:00 IST, which is 05:30 CET. European investors follow it live in the early morning or read the summary.
Afternoon panels
A panel at 15:00 IST is at 10:30 CET. A “convert IST to CET” calculation shows at once that it falls in the first part of the European working day.
The field hockey World Cup
Evening matches
A match that starts at 19:00 IST starts at 14:30 CET. Fans in Germany and the Netherlands watch live in the afternoon.
The final
The final, scheduled for 19:30 IST, is at 15:00 CET. A “convert IST to CET” calculation made beforehand shows that it falls on an ordinary European afternoon.
The Air Force Day flypast
Flying time
The 8 October display begins at 10:00 IST, which is 06:30 CEST. Europeans who follow it live get up early.
The evening programme
The evening ceremony, from 18:00 IST, is at 14:30 CEST. For Central Europe it is an afternoon broadcast.
Dussehra bonfires
Effigies at dusk
The great effigies are lit around 19:00 IST. That is 14:30 CET or 15:30 CEST, depending on the date. Indians living in Switzerland follow the flames on a live stream in the afternoon.
Processions at first light
Morning processions that set off at 08:00 IST are at 03:30 CET. A “convert IST to CET” calculation done with the right date in view gives the true hour on a European clock.
The Rath Yatra at Puri
The chariots set off
The sacred chariots set off around 16:00 IST, which is 12:30 CEST in July. Virtual pilgrims in Europe watch live over lunch.
The evening ritual
The evening rituals, from 19:00 IST, are at 15:30 CEST. For Central Europe it is an afternoon broadcast.
The camel fair at Pushkar
Fair day
The November fair begins at 07:00 IST, which is 02:30 CET. European photographers following online catch it at night or in a recording.
The evening at the fair
Evening shows, from 18:00 IST, are at 13:30 CET. A “convert IST to CET” calculation tells you at once whether you can watch them on your lunch break.
The Hornbill Festival in Nagaland
The December opening
The official opening begins at 09:00 IST, which is 04:30 CET. For Europeans it remains a night broadcast.
Afternoon dances
Afternoon performances, from 14:00 IST, are at 09:30 CET. Whoever does a “convert IST to CET” calculation knows they fall in the European morning.
How to convert IST to CET, in plain terms
Subtract four and a half hours
IST is UTC+5:30 and CET is UTC+1. The European clock stands four and a half hours behind the Indian one. From the Indian time on a 24-hour clock, subtract 4:30. If the result is negative, add 24 and go to the previous day.
Eight pairs
02:00 IST is 21:30 CET the day before. 04:15 IST is 23:45 CET the day before. 05:30 IST is 01:00 CET. 09:15 IST is 04:45 CET. 12:00 IST is 07:30 CET. 16:45 IST is 12:15 CET. 21:00 IST is 16:30 CET. 23:59 IST is 19:29 CET. The first two cross into the previous date.
In the summer months
Between 29 March and 24 October, IST against CEST is three and a half hours: 21:00 IST is 17:30 CEST. It is Europe that changes the clock, not India.
The central European clock, in a few lines
Who uses it
Germany, France, Italy, mainland Spain, Poland, Austria, Switzerland, Hungary, Sweden and Norway read UTC+1 in winter. Between the last Sundays of March and October they read UTC+2 and call it CEST.
The Romanian case
Romania runs an hour ahead of Central Europe, so a reader in Bucharest deducts three and a half hours rather than four and a half.
The Indian clock, in a few lines
A single zone
Gujarat and Assam share one clock, UTC+5:30, in all twelve months. The extra half hour shows up in the minutes of every result: 19:15 IST turns into 14:45 CET.
Next-door countries
Sri Lanka keeps India's hour exactly. Nepal is at UTC+5:45, Pakistan at UTC+5 and Bangladesh at UTC+6.
Four and a half hours between two diaries
Where working days meet
A team in India on a 09:00-17:00 schedule is reachable on Central European clocks from 04:30 to 12:30. A European team with the same schedule is reachable on Indian clocks from 13:30 to 21:30. Only three and a half hours are shared, from 13:30 to 17:00 IST.
Timing a call
Phoning from India at 14:00 IST reaches Europe at 09:30 CET, as the day begins. Phoning at 20:00 IST reaches it at 15:30 CET, with most of the working afternoon still ahead.
A non-stop journey west
A plane that leaves Delhi for Frankfurt at 03:00 IST and flies for nearly nine hours touches down at 12:00 IST, which is 07:30 CET. The boarding pass reads 03:00 and 07:30, as if the flight took four and a half hours.
Banks and insurers with Indian call centres
When the centre starts
An Indian centre that serves European customers opens at 13:30 IST, which is 09:00 CET. A German customer phoning at nine in the morning reaches the Indian afternoon.
When the lines close
Lines shut at 21:30 IST, which is 17:00 CET. A “convert IST to CET” calculation done in advance shows that a call placed after 17:00 CET will not be answered.
One Indian hour on six Fridays
Mid-January
Friday 16 January: 21:00 IST equals 16:30 CET, a gap of four and a half hours.
Either side of the March change
Friday 27 March: 21:00 IST still equals 16:30 CET. Europe advances its clocks on Sunday 29 March while India stays put, so Friday 3 April gives 17:30 CEST and the gap has shrunk to three and a half hours.
Early August
Friday 7 August: 21:00 IST equals 17:30 CEST, three and a half hours apart.
After the autumn change
Friday 30 October, five days after Europe went back to standard time, gives 21:00 IST against 16:30 CET. Friday 18 December gives the same pair.
Why the answer is sometimes an hour smaller
Between spring and autumn
From 29 March to 24 October Central Europe is an hour further forward while India is where it always was. The distance between IST and CET therefore narrows.
The fix
A “convert IST to CET” calculation made with the winter figure comes out an hour early during the European warm season. The correction never varies: add an hour to the answer.
Colleagues in Pune, colleagues in Zurich
The common hour
A team with members in Pune and Zurich meets at 14:30 IST, which is 10:00 CET. For the Indians it is mid-afternoon, for the Swiss the second working hour.
The handover
Work that ends at 17:30 IST reaches Zurich at 13:00 CET, in the middle of the Swiss day. A written handover keeps the thread.
Asian clocks, read from India
How many hours to subtract or add
Relative to Delhi, Dhaka is half an hour ahead, Singapore two and a half hours, Tokyo three and a half, and Dubai an hour and a half behind. Berlin is four and a half hours behind in winter.
A sample invitation
When it is 20:00 in Delhi, it is 18:30 in Dubai, 15:30 in Berlin, 14:30 in London and 23:30 in Tokyo. An invitation with all the hours beside it spares the recipient a “convert IST to CET” calculation of their own.
Live classes from Indian universities
Class hours
A session at 18:00 IST is at 13:30 CET, so European students can join during their lunch break.
Submission cut-offs
A cut-off at 23:59 IST is at 19:29 CET on the same day. Counting it as midnight at home costs whole hours.
Monsoon bulletins, read from Europe
Alert periods
An alert in force until 20:00 IST lapses at 15:30 CET. Relatives in Europe keeping track of family back home deduct four and a half hours from each time in the bulletin.
Which edition is newest
Bulletins are stamped with Indian local time. Passing the stamp through a “convert IST to CET” calculation tells you how long ago the latest edition came out.
When the gap is not the usual one
The 2026 calendar
The difference between IST and CET depends on the date. In 2026: 1 January to 28 March and 25 October to 31 December: CET is 4 hours 30 minutes behind IST; 29 March to 24 October: CET is 3 hours 30 minutes behind IST.
What to do about it
Summer labels are IST and CEST. The form above applies the winter gap of 4 hours 30 minutes, so for other periods correct the answer by the difference from the figure listed. Before you convert IST to CET, find the period that contains your date.
A day of conversions at a glance
IST into CET
00:00 IST corresponds to 19:30 CET (previous day). 01:00 IST corresponds to 20:30 CET (previous day). 02:00 IST corresponds to 21:30 CET (previous day). 03:00 IST corresponds to 22:30 CET (previous day). 04:00 IST corresponds to 23:30 CET (previous day). 05:00 IST corresponds to 00:30 CET. 06:00 IST corresponds to 01:30 CET. 07:00 IST corresponds to 02:30 CET. 08:00 IST corresponds to 03:30 CET. 09:00 IST corresponds to 04:30 CET. 10:00 IST corresponds to 05:30 CET. 11:00 IST corresponds to 06:30 CET. 12:00 IST corresponds to 07:30 CET. 13:00 IST corresponds to 08:30 CET. 14:00 IST corresponds to 09:30 CET. 15:00 IST corresponds to 10:30 CET. 16:00 IST corresponds to 11:30 CET. 17:00 IST corresponds to 12:30 CET. 18:00 IST corresponds to 13:30 CET. 19:00 IST corresponds to 14:30 CET. 20:00 IST corresponds to 15:30 CET. 21:00 IST corresponds to 16:30 CET. 22:00 IST corresponds to 17:30 CET. 23:00 IST corresponds to 18:30 CET.
Using the table
Find the IST hour you need and read off the CET hour beside it. The rows come from the arithmetic behind each request to convert IST to CET. Watch the minutes: a thirty-minute difference means :00 and :30 swap places and the hour is adjusted accordingly. Winter-time arithmetic applies to these rows; for the dates in the period section, correct the result accordingly.
Readings at half past the hour
IST at :30 and the matching CET time
00:30 IST corresponds to 20:00 CET (previous day). 01:30 IST corresponds to 21:00 CET (previous day). 02:30 IST corresponds to 22:00 CET (previous day). 03:30 IST corresponds to 23:00 CET (previous day). 04:30 IST corresponds to 00:00 CET. 05:30 IST corresponds to 01:00 CET. 06:30 IST corresponds to 02:00 CET. 07:30 IST corresponds to 03:00 CET. 08:30 IST corresponds to 04:00 CET. 09:30 IST corresponds to 05:00 CET. 10:30 IST corresponds to 06:00 CET. 11:30 IST corresponds to 07:00 CET. 12:30 IST corresponds to 08:00 CET. 13:30 IST corresponds to 09:00 CET. 14:30 IST corresponds to 10:00 CET. 15:30 IST corresponds to 11:00 CET. 16:30 IST corresponds to 12:00 CET. 17:30 IST corresponds to 13:00 CET. 18:30 IST corresponds to 14:00 CET. 19:30 IST corresponds to 15:00 CET. 20:30 IST corresponds to 16:00 CET. 21:30 IST corresponds to 17:00 CET. 22:30 IST corresponds to 18:00 CET. 23:30 IST corresponds to 19:00 CET.
When to use it
Use these rows for events that begin on the half hour. They follow the same arithmetic as the whole-hour table and spare you another calculation. Read these rows as standard-time values and check the period section for dates where the difference changes.
Ten readings with minutes
Examples from IST to CET
01:05 IST corresponds to 20:35 CET (previous day). 03:20 IST corresponds to 22:50 CET (previous day). 05:50 IST corresponds to 01:20 CET. 07:35 IST corresponds to 03:05 CET. 10:10 IST corresponds to 05:40 CET. 13:25 IST corresponds to 08:55 CET. 16:40 IST corresponds to 12:10 CET. 19:55 IST corresponds to 15:25 CET. 22:15 IST corresponds to 17:45 CET. 23:05 IST corresponds to 18:35 CET.
What to notice
These are less round examples, with minutes. The half-hour in the offset moves each minute reading by thirty, which is why this pair needs a second look. Winter-time arithmetic applies to these rows; for the dates in the period section, correct the result accordingly.
What part of the day is it?
CET equivalents for each IST hour
06:00 IST corresponds to 01:30 CET (night). 08:00 IST corresponds to 03:30 CET (night). 10:00 IST corresponds to 05:30 CET (early morning). 12:00 IST corresponds to 07:30 CET (early morning). 14:00 IST corresponds to 09:30 CET (morning). 16:00 IST corresponds to 11:30 CET (morning). 18:00 IST corresponds to 13:30 CET (around midday). 20:00 IST corresponds to 15:30 CET (afternoon). 22:00 IST corresponds to 17:30 CET (afternoon).
How to use the list
The words in brackets describe the part of the day in CET. They help you avoid planning a call or a task for the middle of the night after you convert IST to CET. These rows use the standard (winter) gap; on the dates listed in the period section the gap is different.
Before you convert IST to CET: a short checklist
Preparation
Read the labels
The letters IST are shared with Ireland’s summer clock and Israel’s standard time; this page means India. A schedule in Warsaw or Madrid in July says CEST, not CET, though the country is the same.
Use a 24-hour clock
Turn a.m. and p.m. into the 24-hour form first: 4:30 p.m. is 16:30 and 12:00 a.m. is 00:00. For example, 09:15 IST becomes 04:45 CET.
Then
The operation
Subtract 4 hours 30 minutes. If the result passes midnight, correct the date: readings before 04:30 fall on the previous date.
A second example
Late in the evening, 22:40 IST becomes 18:10 CET.
Common slips when you convert IST to CET
Adding instead of subtracting
Because CET runs behind IST, the result must be an earlier clock reading. A later one points to an addition.
Losing the date
IST readings before 04:30 fall on the previous 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 IST and CET differs from the usual one, so read the period list before you apply it.
Confusing the abbreviation
IST can also mean Irish Standard Time or Israel Standard Time; here it means India. Do not use CET for Romania, Bulgaria or Greece; they are on Eastern European Time, an hour ahead.
Quick answers
How far apart are IST and CET?
4 hours 30 minutes, and CET is behind IST. That is the standard figure; on some dates in 2026 it differs, as the period list shows.
How do I convert IST to CET?
Subtract 4 hours 30 minutes from the IST time, then fix the date if the result passes midnight.
What is 15:30 IST in CET?
11:00 CET in the standard period.
Does the answer change during the year?
Yes, on some dates; the period list above shows which.
Is my input stored or uploaded?
No. The calculation runs in your browser.
Related conversions
You may also want Convert IST to PST, Convert IST to GMT, Convert GMT to CET, Convert WET to CET, Convert CET to CST, Convert EST to IST, Convert UTC to IST, Convert EET to UTC, Convert EET to IST. To go the other way, use Convert CET to IST.
In brief, to convert IST to CET you subtract 4 hours 30 minutes, mind the date change and watch the weeks when the gap differs.