ACST (Australian Central Standard Time) is UTC+9:30. It is the standard time of Adelaide and Darwin, which switch to ACDT for daylight saving time.
Where and when ACST is used
| IANA time zone | Uses ACST | Main cities |
|---|---|---|
| Australia/Adelaide | Outside daylight saving time | Adelaide |
| Australia/Darwin | All year | Darwin |
ACST and ACDT
ACDT is the daylight saving version of ACST, 1 hour ahead of it. Writing ACST in summer means a time that is 1 hour off for the places that have switched.
Convert ACST to other time zones
Because ACST always means UTC+9:30, each row below is a fixed difference. Check the date only to know whether a place is on ACST at all.
| Zone | UTC offset | When it is 12:00 ACST |
|---|---|---|
| UTC | UTC+0 | 2:30 AM |
| GMT | UTC+0 | 2:30 AM |
| EST | UTC−5 | 9:30 PM (previous day) |
| EDT | UTC−4 | 10:30 PM (previous day) |
| CST | UTC−6 | 8:30 PM (previous day) |
| MST | UTC−7 | 7:30 PM (previous day) |
| PST | UTC−8 | 6:30 PM (previous day) |
| CET | UTC+1 | 3:30 AM |
| CEST | UTC+2 | 4:30 AM |
| EET | UTC+2 | 4:30 AM |
| MSK | UTC+3 | 5:30 AM |
| GST | UTC+4 | 6:30 AM |
| IST | UTC+5:30 | 8:00 AM |
| ICT | UTC+7 | 9:30 AM |
| JST | UTC+9 | 11:30 AM |
| AEST | UTC+10 | 12:30 PM |
| AEDT | UTC+11 | 1:30 PM |
Tools for time in ACST
- Convert a time to or from ACST: pick a date and time and see it in every city on your list.
- Add Adelaide to your world clock to keep it next to your own time.
- Find a meeting time that falls inside office hours in ACST and the other cities you work with.
- Open a full-screen clock for your own time zone.
Frequently asked questions
What is ACST in UTC?
ACST is UTC+9:30. To get UTC, subtract 9 hours 30 minutes from ACST time.
Is it ACST or ACDT right now?
ACST is in use now in Adelaide and Darwin. ACDT returns on Sunday, October 3, 2027.
What time is 12:00 ACST in UTC?
12:00 ACST is 2:30 AM UTC.
Time zone rules: IANA tz database, version 2026e. Place names and coordinates: GeoNames. Sunrise and sunset are calculated from the coordinates and can differ by a minute or two from local almanacs.