Convert ACST to AEDT
AEDT is 1 hour 30 minutes ahead of ACST. ACST is UTC+9:30 and AEDT is UTC+11.
Right now: ACST · AEDT
Best time to schedule a meeting
Standard 9–5 working hours overlap for 7 hours: 9:00 AM–4:00 PM ACST (10:00 AM–5:00 PM AEDT). Schedule meetings inside that window.
| ACST | AEDT | Suitable? |
|---|---|---|
| 9:00 AM | 10:30 AM | working hours |
| 10:00 AM | 11:30 AM | working hours |
| 11:00 AM | 12:30 PM | working hours |
| 12:00 PM | 1:30 PM | working hours |
| 1:00 PM | 2:30 PM | working hours |
| 2:00 PM | 3:30 PM | working hours |
| 3:00 PM | 4:30 PM | working hours |
| 4:00 PM | 5:30 PM | outside 9–5 |
| 5:00 PM | 6:30 PM | outside 9–5 |
ACST to AEDT conversion table
| ACST | AEDT |
|---|---|
| 12:00 AM | 1:30 AM |
| 1:00 AM | 2:30 AM |
| 2:00 AM | 3:30 AM |
| 3:00 AM | 4:30 AM |
| 4:00 AM | 5:30 AM |
| 5:00 AM | 6:30 AM |
| 6:00 AM | 7:30 AM |
| 7:00 AM | 8:30 AM |
| 8:00 AM | 9:30 AM |
| 9:00 AM | 10:30 AM |
| 10:00 AM | 11:30 AM |
| 11:00 AM | 12:30 PM |
| 12:00 PM | 1:30 PM |
| 1:00 PM | 2:30 PM |
| 2:00 PM | 3:30 PM |
| 3:00 PM | 4:30 PM |
| 4:00 PM | 5:30 PM |
| 5:00 PM | 6:30 PM |
| 6:00 PM | 7:30 PM |
| 7:00 PM | 8:30 PM |
| 8:00 PM | 9:30 PM |
| 9:00 PM | 10:30 PM |
| 10:00 PM | 11:30 PM |
| 11:00 PM | 12:30 AM (next day) |
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.
About AEDT
Australian Eastern Daylight Time (AEDT) is UTC+11. It is used in Sydney and Melbourne from October to April.
Australian Eastern Daylight Time is UTC+11, the summer clock for Sydney, Melbourne and Canberra — and summer here means October to April, the opposite half of the year from the northern hemisphere. That inversion is what makes Australia–Europe scheduling awkward: for a few weeks each spring and autumn the two regions are shifting in opposite directions, and the offset between them changes twice within a month.
Does this gap change with the seasons?
This gap is seasonal. The abbreviations themselves are fixed offsets, but the region on AEDT switches to AEST (UTC+10) from April to October. So the 1.5-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 ACST in AEDT?
9:00 AM ACST is 10:30 AM AEDT.
Is AEDT ahead of ACST?
AEDT is 1 hour 30 minutes ahead of ACST.
Which time zone does this use?
ACST is UTC+9:30 and AEDT is UTC+11. 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.