Convert AEST to ACST
ACST is 30 minutes behind AEST. AEST is UTC+10 and ACST is UTC+9:30.
Right now: AEST · ACST
Best time to schedule a meeting
Standard 9–5 working hours overlap for 7 hours: 10:00 AM–5:00 PM AEST (9:00 AM–4:00 PM ACST). Schedule meetings inside that window.
| AEST | ACST | Suitable? |
|---|---|---|
| 9:00 AM | 8:30 AM | outside 9–5 |
| 10:00 AM | 9:30 AM | working hours |
| 11:00 AM | 10:30 AM | working hours |
| 12:00 PM | 11:30 AM | working hours |
| 1:00 PM | 12:30 PM | working hours |
| 2:00 PM | 1:30 PM | working hours |
| 3:00 PM | 2:30 PM | working hours |
| 4:00 PM | 3:30 PM | working hours |
| 5:00 PM | 4:30 PM | working hours |
AEST to ACST conversion table
| AEST | ACST |
|---|---|
| 12:00 AM | 11:30 PM (previous day) |
| 1:00 AM | 12:30 AM |
| 2:00 AM | 1:30 AM |
| 3:00 AM | 2:30 AM |
| 4:00 AM | 3:30 AM |
| 5:00 AM | 4:30 AM |
| 6:00 AM | 5:30 AM |
| 7:00 AM | 6:30 AM |
| 8:00 AM | 7:30 AM |
| 9:00 AM | 8:30 AM |
| 10:00 AM | 9:30 AM |
| 11:00 AM | 10:30 AM |
| 12:00 PM | 11:30 AM |
| 1:00 PM | 12:30 PM |
| 2:00 PM | 1:30 PM |
| 3:00 PM | 2:30 PM |
| 4:00 PM | 3:30 PM |
| 5:00 PM | 4:30 PM |
| 6:00 PM | 5:30 PM |
| 7:00 PM | 6:30 PM |
| 8:00 PM | 7:30 PM |
| 9:00 PM | 8:30 PM |
| 10:00 PM | 9:30 PM |
| 11:00 PM | 10:30 PM |
About AEST
Australian Eastern Standard Time (AEST) is UTC+10. It is used in Sydney, Melbourne and Brisbane in the southern winter.
Australian Eastern Standard Time is UTC+10, covering Sydney, Melbourne, Brisbane and Canberra in winter. The complication is that Queensland does not observe daylight saving while New South Wales and Victoria do — so from October to April, Brisbane stays on AEST while Sydney moves to AEDT, and two cities on the same coast are an hour apart for half the year.
About ACST
Australian Central Standard Time (ACST) is UTC+9:30. It is used in Adelaide and Darwin in winter.
Australian Central Standard Time is UTC+9:30, half an hour behind the eastern states rather than a whole hour, which surprises people every time. South Australia moves to daylight saving in October and the Northern Territory does not, so Adelaide and Darwin share this offset for half the year and are an hour apart for the other half.
Does this gap change with the seasons?
This gap is seasonal. The abbreviations themselves are fixed offsets, but the region on AEST switches to AEDT (UTC+11) from October to April. So the 0.5-hour figure on this page is correct for the part of the year when both places are actually on these abbreviations, and changes by an hour outside it.
ACST does not shift, so the whole change comes from one side. A recurring meeting fixed in ACST will appear to move by an hour for everyone on the other side, twice a year, without anyone changing anything.
This is the reason scheduling systems store an IANA zone such as Region/City rather than an offset or an abbreviation: the zone knows its own rules and the offset does not.
Frequently asked questions
What time is 9:00 AM AEST in ACST?
9:00 AM AEST is 8:30 AM ACST.
Is ACST ahead of AEST?
ACST is 30 minutes behind AEST.
Which time zone does this use?
AEST is UTC+10 and ACST is UTC+9:30. Both abbreviations denote a single fixed offset, so this conversion never shifts with daylight saving — what changes is which abbreviation a place is using at the time.