IST ↔ AEST Time Converter

Australian Eastern Standard Time (AEST) is 4h 30m ahead of India Standard Time (IST). This comes from IST sitting at UTC+5:30 and AEST at UTC+10 / UTC+11 (AEDT). As a quick reference: when it is 9:00 AM in New Delhi, it is 1:30 PM in Sydney. At noon in New Delhi (12:00 PM), Sydney reads 4:30 PM. And 5:00 PM in New Delhi corresponds to 9:30 PM in Sydney.

To convert IST to AEST by hand, add 4 hours 30 minutes to the IST time. For example, 12:00 PM IST becomes 4:30 PM AEST. If the result goes past midnight, increment (or decrement) the calendar date accordingly — the converter on this page flags this with a "+1 Day" or "-1 Day" note automatically. For half-hour or 45-minute offsets, just carry the minutes over normally (e.g., 30 extra minutes means the result's minutes increase by 30, rolling over to the next hour if needed).

Australian Eastern Standard Time (AEST) is 4h 30m ahead of India Standard Time (IST). Flipped the other way, IST is 4h 30m behind of AEST. A practical example: if someone in Sydney says "let's meet at noon," that maps to 7:30 AM IST in New Delhi.

India Standard Time (IST) is the civil time standard used across New Delhi, Mumbai, Bangalore, Chennai and nearby regions. It sits at UTC+5:30 relative to Coordinated Universal Time (UTC). It does not observe Daylight Saving Time, meaning the UTC offset stays constant at UTC+5:30 all year — every day of the year. The zone encompasses major cities including New Delhi, Mumbai, Bangalore, Chennai, Kolkata, Hyderabad, Colombo.

Australian Eastern Standard Time (AEST) is the standard time used in Sydney, Melbourne, Brisbane, Canberra and surrounding areas. It operates at UTC+10 / UTC+11 (AEDT) from UTC. It observes Daylight Saving Time, so the effective offset shifts by one hour during parts of the year. Cities in this zone include Sydney, Melbourne, Brisbane, Canberra, Hobart, Newcastle, Gold Coast.

Yes. AEST observes Daylight Saving Time and moves its clocks by one hour during summer, while IST stays fixed at UTC+5:30 year-round. This means the gap changes seasonally — it shifts by one hour when AEST transitions in or out of its daylight period. The live converter on this page always shows the accurate current offset.

The ideal meeting window is where standard business hours (roughly 9 AM – 6 PM) overlap in both zones. Given that AEST is 4h 30m ahead of IST, mornings on the earlier side tend to align with afternoons on the later side. As a general rule: aim for 8 AM – 11 AM in the earlier zone to keep both sides in reasonable working hours. See the meeting hours table above for exact recommended slots for this specific pair. Avoid times that push either side before 7 AM or after 9 PM — those are shaded in the table.

Type any time directly into the AEST input field in the bidirectional converter above — it calculates the IST equivalent instantly and works equally well in both directions. Alternatively, subtract 4 hours 30 minutes from the AEST time to get the IST result manually. You can also visit the dedicated reverse page: AEST to IST converter ↗.

For certain hours, the conversion can cross midnight into the next or previous calendar day. When a converted time goes past 11:59 PM or before 12:00 AM, the date changes. The converter on this page shows a "+1 Day" label when the result falls on the next calendar day, and "-1 Day" when it falls the previous day. Always check this when sending calendar invites across these two zones — booking a "Tuesday 3 PM" meeting can accidentally land on Wednesday or Monday in the other zone if you miss the date shift.

India Standard Time (IST) is used across the following cities and regions: New Delhi, Mumbai, Bangalore, Chennai, Kolkata, Hyderabad, Colombo. The zone covers UTC+5:30, with no seasonal change — the same offset applies every day of the year. It is one of the major time zones used for international scheduling and business.

Australian Eastern Standard Time (AEST) covers Sydney, Melbourne, Brisbane, Canberra, Hobart, Newcastle, Gold Coast among other locations. Running at UTC+10 / UTC+11 (AEDT)and observing Daylight Saving Time seasonally, it is the civil time standard for this part of the world. When coordinating across IST and AEST, use the live clocks at the top of this page to confirm the exact current local time in both zones before finalising any schedule.

India Standard Time (IST) uses a UTC+5:30 offset — a 30-minute offset from the nearest whole hour — because India chose a single national time zone that best approximates local solar noon across the country's large east-west span. The half-hour offset is a deliberate compromise that puts most of the country within 30 minutes of solar noon, rather than forcing two separate time zones.

Yes — the converter on this page is designed for exactly that. The live clocks update every second so you always see the current time in both zones at a glance. The editable input fields let you test any time instantly, and the 24-hour table gives you a quick reference for the whole day. For recurring meetings, the best approach is to pick a slot from the "Best Meeting Hours" table above and then lock it in your calendar with the correct timezone so it self-adjusts for any DST transitions automatically.