ACDT — Australian Central Daylight Time
ACDT is Australian Central Daylight Time, 10 hours 30 minutes ahead of UTC. It is a fixed offset: unlike a time zone, it does not change with the season — the zones that use it switch to a different abbreviation instead.
Current time in ACDT
18:16
Sunday, 2 August 2026
ACDT = UTC+10:30 · 10 hours 30 minutes ahead of UTC
Shown for 2 Aug 2026 07:46 UTC. The clock goes live as soon as scripts load.
UTC offset
UTC+10:30
Type
Daylight saving
Seasonal counterpart
ACST
The letters the same zones use for the other half of the year
Meanings
1
Unambiguous
Is ACDT in force right now?
A zone only carries this abbreviation for part of the year. This is which of them were on it at 2 Aug 2026 07:46 UTC; the list is re-derived against your own clock when scripts load.
On ACDT now
- No zone was using ACDT at that moment.
Using a different abbreviation
- Australia/Adelaide — on ACST (UTC+9:30)
ACDT alternates with ACST across the year.
Writing “ACDT” for a date in the other half of the year is the most common time zone mistake in meeting invitations.
Convert ACDT to other time zones
City clocks reflect whatever their zone is doing; where a city observes daylight saving time, its difference from ACDT changes twice a year. Use the time zone converter for a specific date.
Time zones and cities that use ACDT
Australian Central Daylight Time · UTC+10:30
Why ACDT is not an identifier
ACDT is shorthand, not a standard. There is no registry of time zone abbreviations, no authority that assigns them, and nothing preventing two regions from adopting the same three letters — which is what makes codes like IST and CST unusable without context.
For anything a machine will read — a calendar invitation, a database column, an API response — use the IANA identifier of the zone (Australia/Adelaide, for example) or an explicit UTC offset alongside the date. The identifier survives a change in the law; ACDT and its 10 hours 30 minutes offset do not.
Frequently asked questions
What does ACDT stand for?
ACDT stands for Australian Central Daylight Time. It is 10 hours 30 minutes ahead of UTC, written UTC+10:30.
What is ACDT in UTC?
ACDT is UTC+10:30. To convert an ACDT time to UTC, subtract 10 hours 30 minutes.
What is the difference between ACDT and ACST?
ACDT is the daylight saving form and ACST the standard form of the same zones. The two are one hour apart and only one is ever in force at a time, so a recurring meeting written "ACDT" shifts by an hour when the clocks change.
Which time zone should I use instead of ACDT?
Use an IANA identifier — Australia/Adelaide for Australian Central Daylight Time — or state the UTC offset with the date. Abbreviations are not identifiers: they are not unique, they are not registered anywhere, and half of them change with the season. Calendar software resolves this automatically when you pick a city rather than typing letters.