India Standard Time (ist) is used in India. The IANA timezone identifier is Asia/Kolkata.

Australian Eastern Standard Time (aest) is used in Australia. The IANA timezone identifier is Australia/Brisbane.

IST to AEST Time Converter

India Standard Time → Australian Eastern Standard Time

IST = UTC+5:30AEST = UTC+10

⚠️ IST is ambiguous — on this page it means India Standard Time. It also refers to:

Ireland Standard Time (Dublin) → AEST ↗Israel Standard Time (Jerusalem) → AEST ↗

ClockinSync

BASE

09:00

Work Clients Team +

00:0006:0012:0018:0024:00

AEST (Brisbane)

Australia · +4.5h

13:30

London

United Kingdom · -4.5h

04:30

New York

USA · -9.5h

23:30-1 day

Tokyo

Japan · +3.5h

12:30

Dubai

United Arab Emirates · -1.5h

07:30

IST (Mumbai) ↔ AEST (Brisbane) — time offset

IST (Mumbai) is 5 hours 30 minutes behind AEST (Brisbane). At noon in IST (Mumbai), your contact in AEST (Brisbane) sees 16:00.

IST (Mumbai) observes Asia/Kolkata and AEST (Brisbane) observes Australia/Brisbane — a 4.5 hours 30 minutes gap between them.

Mutual working hours

IST (Mumbai) and AEST (Brisbane) share 3.5 hours of overlapping business hours daily — enough for real-time collaboration without anyone joining at odd hours.

00:0006:0012:0018:0024:00

IST (Mumbai)

AEST (Brisbane)

Overlap (3.5h)

Meeting time recommendations

IST (Mumbai) and AEST (Brisbane) share 3.5 hours of business hours overlap daily. Showing the 3 most balanced slots — see the time table below for the full window.

09:00 Mumbai / 13:00 Brisbane✓ Both working

10:00 Mumbai / 14:00 Brisbane✓ Both working

11:00 Mumbai / 15:00 Brisbane✓ Both working

Assumes a standard 9 AM–5 PM workday in each location's local timezone.

Public holidays for both locations

IST (Mumbai)

No upcoming public holidays this year.

AEST (Brisbane)7 holidays

Aug 3Picnic Day

Sep 28King's Birthday

Oct 5Labour Day

Oct 5King's Birthday

Nov 3Melbourne Cup

Scheduling between IST (Mumbai) and AEST (Brisbane)

Teams in IST (Mumbai) (India) and AEST (Brisbane) (Australia) face a 4.5-hour time difference day to day. A 3.5-hour shared business hours window makes real-time meetings feasible for both sides within their normal working day.

💡 Scheduling tips for these locations

✅

Schedule at 09:00–10:00 (IST (Mumbai)) for a 13:00–14:00 slot in AEST (Brisbane) — the sweet spot where both teams are working.

✅

Schedule at 10:00–11:00 (IST (Mumbai)) for a 14:00–15:00 slot in AEST (Brisbane) — the sweet spot where both teams are working.

✅

Schedule at 11:00–12:00 (IST (Mumbai)) for a 15:00–16:00 slot in AEST (Brisbane) — the sweet spot where both teams are working.

Recurring meetings are particularly vulnerable to DST shifts. The ClockinSync Chrome Extension alerts you before the offset changes.

Install ClockinSync Free →

Drag the slider at the top to convert any IST (Mumbai) time instantly. You can also type natural language like "3pm", "15:00", or a location name to get an immediate answer.

IST (Mumbai) ↔ AEST (Brisbane)

4h of business hours overlap daily (09:00–17:00)

IST (Mumbai)

AEST (Brisbane)

00:00

04:30

01:00

05:30

02:00

06:30

03:00

07:30

04:00

08:30

05:00

09:30Working

06:00

10:30Working

07:00

11:30Working

08:00

12:30Working

09:00Working

13:30Working

10:00Working

14:30Working

11:00Working

15:30Working

12:00Working

16:30Working

13:00Working

17:30off

14:00Working

18:30off

15:00Working

19:30off

16:00Working

20:30off

17:00

21:30

18:00

22:30

19:00

23:30

20:00

00:30+1d

21:00

01:30+1d

22:00

02:30+1d

23:00

03:30+1d

Working hours: 09:00–17:00 local. Green = both working. Purple = one side only.

Frequently Asked Questions

What is the difference between ist and aest?

India Standard Time (ist) is UTC+5:30 and Australian Eastern Standard Time (aest) is UTC+10. The difference between them is 4.5 hours.

Where is ist used?

India Standard Time (ist) is used in India and surrounding regions. The IANA timezone identifier is Asia/Kolkata. Note: ist is ambiguous and may refer to other timezones.

Where is aest used?

Australian Eastern Standard Time (aest) is used in Australia and surrounding regions. The IANA timezone identifier is Australia/Brisbane.

How do I convert ist to aest?

Use the interactive converter above. Drag the time slider to any ist time and the aest equivalent updates instantly. You can also type a time like "3pm" or "15:00" in the input bar.

Popular IST conversions

IST → London IST → New York IST → Tokyo IST → Dubai IST → Sydney IST → Paris IST → Berlin IST → Singapore IST → Los Angeles IST → Toronto

Popular AEST conversions

London → AEST New York → AEST Tokyo → AEST Dubai → AEST Sydney → AEST Paris → AEST Berlin → AEST Singapore → AEST Los Angeles → AEST Toronto → AEST