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ACDT to AST Converter

From Australian Central Daylight Time to Atlantic Standard Time: aST is 14 hours and 30 minutes behind ACDT. Use the editable converter to translate any ACDT time — including the date — into AST.

ADT is 12 hours 30 min behind ACST−1 day
From
ACST

Now in Adelaide: 3:24:05 AM ACST

On this date Adelaide observes ACST. ACDT is in effect during summer (daylight saving) months.

To
−1 day
ADT

Now in Halifax: 2:54:05 PM ADT

On this date Halifax observes ADT. AST is in effect during standard-time (non-summer) months.

Jump to:

Daylight saving notes

In southern Australia, daylight saving time runs from the first Sunday in October to the first Sunday in April. That affects Australian Central Daylight Time (ACDT).

In the United States and Canada, daylight saving time runs from the second Sunday in March to the first Sunday in November. That affects Atlantic Standard Time (AST).

ACDT to AST conversion chart

For example, a 9:00 AM ACDT meeting takes place at 6:30 PM AST (−1 day). Concretely, when Adelaide (ACDT) and Halifax (AST) set up a call, aST is 14 hours and 30 minutes behind ACDT.

Australian Central Daylight Time to Atlantic Standard Time conversion chart
ACDT timeAST time
12:00 AM9:30 AM−1 day
1:00 AM10:30 AM−1 day
2:00 AM11:30 AM−1 day
3:00 AM12:30 PM−1 day
4:00 AM1:30 PM−1 day
5:00 AM2:30 PM−1 day
6:00 AM3:30 PM−1 day
7:00 AM4:30 PM−1 day
8:00 AM5:30 PM−1 day
9:00 AM6:30 PM−1 day
10:00 AM7:30 PM−1 day
11:00 AM8:30 PM−1 day
12:00 PM9:30 PM−1 day
1:00 PM10:30 PM−1 day
2:00 PM11:30 PM−1 day
3:00 PM12:30 AM
4:00 PM1:30 AM
5:00 PM2:30 AM
6:00 PM3:30 AM
7:00 PM4:30 AM
8:00 PM5:30 AM
9:00 PM6:30 AM
10:00 PM7:30 AM
11:00 PM8:30 AM

This chart uses the fixed ACDT and AST offsets; the live converter above follows current daylight saving.

Convert ACDT to AST Time Zone

A quick guide to ACDT → AST: the time gap, the live clocks, scheduling tips, and how we keep it accurate.

Converting ACDT to AST, step by step

It takes three quick steps:

  1. Click the ACDT field on the left and pick the time you want to convert.
  2. The matching AST time updates on the right automatically — there’s no button to press.
  3. Need a different day? Click the date field and the result follows, rolling over if it crosses midnight.

How many hours apart are ACDT and AST?

AST is 14 hours and 30 minutes behind ACDT. In everyday terms, once you know the time on one side you just subtract 14 hours 30 min to get the other — so a call between Adelaide and Halifax is always 14 hours 30 min apart.

What's the current time in AST?

Right now the time in Atlantic Standard Time (AST) is Monday, June 29, 2026 · 1:54:05 PM. It ticks every second, so you’re always looking at the live AST clock.

And what time is it in ACDT?

And in Australian Central Daylight Time (ACDT), it’s currently Tuesday, June 30, 2026 · 4:24:05 AM. Compare the two and the 14 hours 30 min gap is easy to see.

What's the best time for a ACDT–AST call?

For example, a 9:00 AM ACDT meeting takes place at 6:30 PM AST (−1 day). The trick is to aim for a slot that lands inside normal working hours on both sides. Once you’ve found a time, hit Share on the converter to copy a link with the time built in — easy to send to a colleague. Juggling three or more zones? The meeting planner highlights the hours that overlap for everyone.

Does daylight saving time change the ACDT–AST difference?

The labels ACDT and AST are fixed offsets, so the result on this page is always exact. Both regions move their clocks for daylight saving on roughly the same weekends, so the 14 hours 30 min gap usually holds steady right through the year.

How accurate is this ACDT to AST conversion?

We don’t guess. ACDT and AST times are worked out from the official IANA time zone database, the trusted standard that operating systems use worldwide. Because daylight-saving rules and regional offsets do change over time, we track those updates rather than relying on a fixed number — which is exactly where many converters slip up.

Convert ACDT to other time zones

Convert to AST from other time zones

Frequently asked questions

How many hours behind ACDT is AST?

AST is 14 hours and 30 minutes behind ACDT — a fixed 14 hours and 30 minutes difference, since both are fixed-offset labels.

What time is it in AST when it's 12:00 PM ACDT?

When it's 12:00 PM (noon) ACDT, it's 9:30 PM AST the previous day.

Do ACDT or AST use daylight saving time?

Australian Central Daylight Time (ACDT) observes daylight saving, alternating with ACST; Atlantic Standard Time (AST) observes daylight saving, alternating with ADT.

Why might the real-world ACDT–AST difference change during the year?

The labels ACDT and AST are fixed offsets, so this converter is always exact. But Australian Central Daylight Time's region switches between standard and summer time, so for part of the year you may actually want ACST to AST. Always check which label a region is currently using before you schedule.