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 AEST

+4h 30m

IST

ISTSOURCE

UTC+05:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

AEST

UTC+10:00DST observed

HH04

MM30

16:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

IST

AEST

12:00 AM

4:30 AM

2:00 AM

6:30 AM

4:00 AM

8:30 AM

6:00 AM

10:30 AM

8:00 AM

12:30 PM

10:00 AM

2:30 PM

12:00 PM

4:30 PM

2:00 PM

6:30 PM

4:00 PM

8:30 PM

6:00 PM

10:30 PM

8:00 PM

12:30 AM+1

10:00 PM

2:30 AM+1

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

IST and AEST on the World Map

The map below highlights the IST (India Standard Time) and AEST (Australian Eastern Standard Time) timezone regions across the globe.

IST Zone

→

AEST 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

AEST – Australian Eastern Standard Time

UTC+10:00

Australian Eastern Standard Time (AEST) covers eastern Australia, 10 hours ahead of UTC.

Countries in AEST

Australia (NSW, VIC, QLD, TAS, ACT)Papua New Guinea

Major Cities in AEST

SydneyMelbourneBrisbaneCanberraHobartGold Coast

Key Facts about AEST

•Queensland does not observe daylight saving time, staying on AEST year-round.
•Sydney and Melbourne switch to AEDT (UTC+11:00) in summer.
•The Australian Securities Exchange (ASX) operates on AEST/AEDT.
•AEST is 15 hours ahead of EST during winter.

Daylight Saving:Yes – switches to AEDT

Learn more about AEST on Wikipedia

Everything You Need to Know About IST and AEST Time

IST runs on India Standard Time (IST) at UTC+05:30. AEST runs on Australian Eastern Standard Time (AEST) at UTC+10:00. That puts IST 4 hours 30 minutes ahead of AEST — a difference of +4h 30m at the current offsets.

In practice, when it is 9:00 AM in IST it is 1:30 PM in AEST. Midnight in IST is 4:30 AM in AEST. Neither zone observes daylight saving time, so the offset between them stays constant all year.

IST to AEST time conversion table

IST (IST)	AEST (AEST)	Day
12:00 AM	4:30 AM	same day
6:00 AM	10:30 AM	same day
7:00 AM	11:30 AM	same day
8:00 AM	12:30 PM	same day
9:00 AM	1:30 PM	same day
12:00 PM	4:30 PM	same day
3:00 PM	7:30 PM	same day
5:00 PM	9:30 PM	same day
6:00 PM	10:30 PM	same day
9:00 PM	1:30 AM	next day

Why people convert IST to AEST time

Scheduling a call from IST to AEST: a 10:00 AM start in IST lands at 2:30 PM in AEST, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both IST and AEST are inside the 9-to-5 working day between 9:00 AM and 12:30 PM IST time (1:30 PM–5:00 PM AEST). That is roughly 3 hours 30 minutes of usable overlap.
Keeping family and friends in sync: knowing that 8:00 PM in IST is 12:30 AM in AEST 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 +4h 30m gap is not.
Block 9:00 AM–12:30 PM IST as the recurring meeting window if you work primarily from IST and need AEST 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 AEST (Australian Eastern Standard Time)

Australian Eastern Standard Time (AEST) is used in the eastern states of Australia including New South Wales, Victoria, Queensland, Tasmania, and the ACT. During summer (October to April), NSW, VIC, TAS, and ACT switch to Australian Eastern Daylight Time (AEDT, UTC+11:00), while Queensland remains on AEST year-round.

Best time to call between IST and AEST

Both IST and AEST sit inside the 9 AM – 5 PM working day between 9:00 AM–12:30 PM IST, which is 1:30 PM–5:00 PM AEST. That gives roughly 3 hours and 30 minutes of shared time — the safest window for a live call or meeting.

Business hours overlap

IST and AEST overlap for about 3 hours during the working day — enough for meetings if you avoid the edges of the window.

IST is 4 hours 30 minutes ahead of AEST (IST UTC+05:30 → AEST UTC+10:00). The shared working window is 9:00 AM–12:30 PM IST. Remember to re-check around daylight-saving transitions.

🕐 Daylight Saving Time Info

IST

Does not observe DST

AEST

❄ Currently in Standard Time

Standard: UTC+10:00 · DST: UTC+11:00

Clocks spring forward on Sat, Oct 3, 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 AEST?

IST (IST, UTC+05:30) is 4 hours 30 minutes ahead of AEST (AEST, UTC+10:00). The gap is currently +4h 30m.

How do I convert IST time to AEST time?

Add +4h 30m to IST local time. For example, 9:00 AM in IST is 1:30 PM in AEST.

What time is it in AEST right now?

AEST uses AEST at UTC+10:00. Use the live converter at the top of this page — it updates in real time and already accounts for the +4h 30m offset from IST.