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 CAT

-3h 30m

IST

ISTSOURCE

UTC+05:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

CAT

UTC+02:00

HH08

MM30

08:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

IST

CAT

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 CAT on the World Map

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

IST Zone

→

CAT 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

CAT – Central Africa Time

UTC+02:00

Central Africa Time (CAT, UTC+02:00) covers Zimbabwe, Zambia, Mozambique, Malawi and neighbouring countries.

Countries in CAT

ZimbabweZambiaMozambiqueMalawiRwandaBurundiDR Congo (east)

Major Cities in CAT

HarareLusakaMaputoLilongweKigali

Key Facts about CAT

•Central Africa Time is fixed at UTC+02:00 with no daylight saving.
•CAT matches South Africa Standard Time (SAST) all year.
•It is the same offset as Central European Time in winter.
•Harare is level with Johannesburg and one hour ahead of Lagos.

Daylight Saving:No – UTC+02:00 year-round

Learn more about CAT on Wikipedia

IST vs CAT: Offsets, DST and Best Call Times

IST runs on India Standard Time (IST) at UTC+05:30. CAT runs on Central Africa Time (CAT) at UTC+02:00. That puts IST 3 hours 30 minutes behind CAT — 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 CAT. Midnight in IST is 8:30 PM in CAT. Neither zone observes daylight saving time, so the offset between them stays constant all year.

IST to CAT time conversion table

IST (IST)	CAT (CAT)	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 CAT time

Scheduling a call from IST to CAT: a 10:00 AM start in IST lands at 6:30 AM in CAT, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both IST and CAT are inside the 9-to-5 working day between 12:30 PM and 5:00 PM IST time (9:00 AM–1:30 PM CAT). That is roughly 4 hours 30 minutes of usable overlap.
Keeping family and friends in sync: knowing that 8:00 PM in IST is 4:30 PM in CAT makes it easy to avoid calling at 3 AM.

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 CAT colleagues present.

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 CAT (Central Africa Time)

Central Africa Time (CAT) is fixed at UTC+02:00 all year across a broad belt of southern and central Africa, including Zimbabwe, Zambia, Mozambique, Malawi, Rwanda, Burundi and the eastern Democratic Republic of the Congo. None of these countries observes daylight saving time, so CAT never shifts. It is the same offset as South Africa Standard Time (SAST) and the winter version of Central European Time, which makes CAT a convenient bridge between African, European and Middle Eastern schedules — Harare is level with Johannesburg all year and one hour ahead of Lagos.

Best time to call between IST and CAT

Both IST and CAT 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 CAT. 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 CAT 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 CAT (IST UTC+05:30 → CAT UTC+02:00). The shared working window is 12:30 PM–5:00 PM IST. Remember to re-check around daylight-saving transitions.

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 CAT?

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

How do I convert IST time to CAT time?

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

What time is it in CAT right now?

CAT uses CAT 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.