Does it account for Daylight Saving Time?

Yes, our converter uses the IANA timezone database, which includes all current DST rules for every timezone in the world.

UTC (Coordinated Universal Time) is the primary time standard by which the world regulates clocks. All timezones are defined as offsets from UTC.

Can I compare multiple timezones at once?

Yes, you can add multiple cities or timezones and see the equivalent times side by side.

How many timezones are there in the world?

There are 38 distinct UTC offsets in use, ranging from UTC-12 to UTC+14. This includes half-hour (UTC+5:30 India, UTC+9:30 Australia) and 45-minute offsets (UTC+5:45 Nepal, UTC+8:45 Australia).

What is the International Date Line?

The International Date Line (IDL) runs roughly along the 180° meridian in the Pacific Ocean. When you cross it westward, you gain a day; crossing eastward, you lose a day.

Why do some timezones have 30 or 45 minute offsets?

Countries chose offsets that best matched their solar noon. India uses UTC+5:30 and Nepal uses UTC+5:45 because standard hourly offsets didn't align well with their geography.

Which country has the most timezones?

France has the most (12 timezones) due to overseas territories. Russia spans 11 timezones. The US has 6 (including Hawaii and Alaska).

IST to Vienna

-3h 30m

IST

ISTSOURCE

UTC+05:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Vienna

CEST

Austria · UTC+02:00☀ DST active

HH08

MM30

08:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

IST

Vienna

12:00 AM

8:30 PM-1

2:00 AM

10:30 PM-1

4:00 AM

12:30 AM

6:00 AM

2:30 AM

8:00 AM

4:30 AM

10:00 AM

6:30 AM

12:00 PM

8:30 AM

2:00 PM

10:30 AM

4:00 PM

12:30 PM

6:00 PM

2:30 PM

8:00 PM

4:30 PM

10:00 PM

6:30 PM

Green rows indicate typical business hours (9 AM - 5 PM)

IST and CEST on the World Map

The map below highlights the IST (India Standard Time) and CEST (Central European Time) timezone regions across the globe.

IST Zone

→

CEST Zone

Explore all world timezones interactively →

IST – India Standard Time

UTC+05:30

India Standard Time (IST) is the time zone for India and Sri Lanka, 5 hours and 30 minutes ahead of UTC.

Countries in IST

IndiaSri Lanka

Major Cities in IST

MumbaiDelhiBangaloreKolkataChennaiHyderabadPuneAhmedabadColomboJaipurLucknowSurat

Key Facts about IST

•India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT.
•India uses a single time zone despite spanning 30° of longitude.
•IST is one of only a handful of time zones with a 30-minute offset.
•IST is the most populous single time zone in the world with over 1.4 billion people.
•The Bombay Stock Exchange (BSE) and National Stock Exchange (NSE) operate on IST.

Daylight Saving:No – UTC+05:30 year-round

Learn more about IST on Wikipedia

CET – Central European Time

UTC+01:00

Central European Time (CET) is used across most of Western and Central Europe, 1 hour ahead of UTC.

Countries in CET

GermanyFranceItalySpainNetherlandsBelgiumAustriaSwitzerlandPolandCzech RepublicSwedenNorwayDenmarkHungaryCroatiaSerbiaSlovakiaSloveniaBosnia and HerzegovinaNorth MacedoniaAlbaniaMontenegroLuxembourgMaltaTunisiaAlgeriaNigeria

Major Cities in CET

ParisBerlinRomeMadridAmsterdamBrusselsViennaWarsawZurichStockholmOsloCopenhagenPragueBudapestBarcelonaMunichMilanLagos

Key Facts about CET

•CET covers more European countries than any other time zone.
•Spain uses CET despite being geographically aligned with GMT/WET.
•The Frankfurt Stock Exchange, Euronext (Amsterdam/Paris), and Borsa Italiana operate on CET.
•Over 500 million people live in the CET time zone.
•France moved to CET during the German occupation in WWII and never switched back.

Daylight Saving:Yes – switches to CEST

Learn more about CET on Wikipedia

About Vienna

Wikipedia

Vienna operates on Central European Time (CET/CEST). As a major EU hub and headquarters for international organizations, Vienna coordinates Central European business.

Population:1.9 million

Metro:2.9 million

Business Hours:8:00 AM - 5:00 PM CET

Currency:EUR (€)

Stock Exchange:Wiener Börse

Key Landmarks

Schönbrunn PalaceSt. Stephen's CathedralBelvedere PalaceHofburgVienna State Opera

Did You Know?

Vienna has more than 50 theaters and opera houses.

Learn more about CEST timezone →

Comparing Time Zones: IST and Vienna

IST runs on India Standard Time (IST) at UTC+05:30. Vienna runs on Central European Summer Time (CEST) at UTC+02:00, also currently on daylight saving time. That puts IST 3 hours 30 minutes behind Vienna — a difference of -3h 30m at the current offsets.

In practice, when it is 9:00 AM in IST it is 5:30 AM in Vienna. Midnight in IST is 8:30 PM in Vienna.Vienna observes daylight saving time while IST does not, so the gap narrows or widens by an hour part of the year.

IST to Vienna time conversion table

IST (IST)	Vienna (CEST)	Day
12:00 AM	8:30 PM	previous day
6:00 AM	2:30 AM	same day
7:00 AM	3:30 AM	same day
8:00 AM	4:30 AM	same day
9:00 AM	5:30 AM	same day
12:00 PM	8:30 AM	same day
3:00 PM	11:30 AM	same day
5:00 PM	1:30 PM	same day
6:00 PM	2:30 PM	same day
9:00 PM	5:30 PM	same day

Why people convert IST to Vienna time

Scheduling a call from IST to Vienna: a 10:00 AM start in IST lands at 6:30 AM in Vienna, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both IST and Vienna are inside the 9-to-5 working day between 12:30 PM and 5:00 PM IST time (9:00 AM–1:30 PM CEST). That is roughly 4 hours 30 minutes of usable overlap.
Watching a live event or market open: IST viewers need 5:30 AM in Vienna to catch a 9:00 AM start there, and 3:30 AM if the event is anchored to IST.

Always state the zone abbreviation, not just the hour. "3:00 PM IST" is unambiguous; "3 PM" across a -3h 30m gap is not.
Block 12:30 PM–5:00 PM IST as the recurring meeting window if you work primarily from IST and need Vienna colleagues present.
Vienna: Clocks fall back on Sun, Oct 25, 2026. Any meeting series spanning that date will shift by an hour in local time.

About IST (India Standard Time)

India Standard Time (IST) is the time observed throughout India and Sri Lanka. It is based on the 82.5°E meridian, passing through Mirzapur in Uttar Pradesh. India uses a single time zone despite spanning roughly 30° of longitude, which has been debated. IST does not observe daylight saving time. India is the world's most populous country, making IST one of the most-used time zones globally. The IT outsourcing industry and call centers operate primarily on IST, making the EST-to-IST conversion one of the most searched timezone conversions.

About CET (Central European Time)

Central European Time (CET) is the standard time zone for most of Europe, covering over 30 countries from Spain to Poland, and from Norway to Italy. CET is 1 hour ahead of GMT and is used by the European Union's most populous nations. During summer, most CET countries switch to Central European Summer Time (CEST, UTC+02:00). Major European financial markets in Frankfurt, Paris, and Amsterdam operate on CET.

Best time to call between IST and Vienna

Both IST and Vienna sit inside the 9 AM – 5 PM working day between 12:30 PM–5:00 PM IST, which is 9:00 AM–1:30 PM CEST. That gives roughly 4 hours and 30 minutes of shared time — the safest window for a live call or meeting.

Business hours overlap

IST and Vienna overlap for about 4 hours during the working day — enough for meetings if you avoid the edges of the window.

IST is 3 hours 30 minutes behind Vienna (IST UTC+05:30 → CEST UTC+02:00). The shared working window is 12:30 PM–5:00 PM IST. Remember to re-check around daylight-saving transitions.

🕐 Daylight Saving Time Info

IST

Does not observe DST

Vienna

☀ Currently in DST

Standard: UTC+01:00 · DST: UTC+02:00

Clocks fall back on Sun, Oct 25, 2026

Learn More About Time

Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:

⏳

History of Timekeeping

From sundials to atomic clocks - 5000 years of measuring time

🌍

How Time Zones Work

UTC, offsets, and why zones don't follow straight lines

☀️

Daylight Saving Time

DST dates, which countries observe it, and the ongoing debate

Frequently Asked Questions

What is the time difference between IST and Vienna?

IST (IST, UTC+05:30) is 3 hours 30 minutes behind Vienna (CEST, UTC+02:00). The gap is currently -3h 30m.

How do I convert IST time to Vienna time?

Add -3h 30m to IST local time. For example, 9:00 AM in IST is 5:30 AM in Vienna.

What time is it in Vienna right now?

Vienna uses CEST at UTC+02:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -3h 30m offset from IST.

What is the best time to call Vienna from IST?

Call between 12:30 PM and 5:00 PM IST — that maps to 9:00 AM–1:30 PM CEST and keeps both parties inside the working day.

Which is behind, IST or Vienna?

IST is 3 hours 30 minutes behind Vienna. When it is 12:00 PM in IST it is 8:30 AM in Vienna.

Do IST and Vienna use different time zones?

IST uses IST at UTC+05:30, while Vienna (Austria) uses CEST at UTC+02:00. The IANA identifiers are Asia/Kolkata and Europe/Vienna.

Does daylight saving time affect the IST–Vienna difference?

Yes at the moment: Vienna is on daylight saving time and IST is not, so the -3h 30m gap shifts by an hour when exactly one of them changes clocks.

Which other cities share IST's time zone?

IST also covers Mumbai, Delhi, Bangalore, Kolkata, Chennai, Hyderabad, Pune, Ahmedabad and 4 more.

Which countries use IST, IST's zone?

IST is used in India, Sri Lanka.

Is there a day difference between IST and Vienna?

Not normally. The -3h 30m gap only pushes the date over the previous day.

What is the time difference between IST and Vienna?

Vienna is -3h 30m from IST.

What timezone is IST in?

IST operates on its local timezone.

What timezone is Vienna in?

Vienna operates on Central European Time (CET/CEST). As a major EU hub and headquarters for international organizations, Vienna coordinates Central European business.