PDT to ACST
+16h 30mPDT
PDTSOURCEACST
ACSTGreen rows indicate typical business hours (9 AM - 5 PM)
PDT and ACST on the World Map
The map below highlights the PDT (Pacific Daylight Time) and ACST (Australian Central Standard Time) timezone regions across the globe.
PDT – Pacific Daylight Time
UTC-07:00Pacific Daylight Time (PDT) is the daylight saving offset on the US/Canada Pacific coast, 7 hours behind UTC.
- •PDT aligns with MST at UTC-07:00.
- •Tech company earnings calls often reference PDT/PST times.
ACST – Australian Central Standard Time
UTC+09:30Australian Central Standard Time (ACST, UTC+09:30) covers South Australia and the Northern Territory, on a half-hour offset.
- •ACST uses a half-hour offset: UTC+09:30.
- •South Australia moves to ACDT (UTC+10:30) in summer; the Northern Territory does not.
- •Adelaide and Darwin are 30 minutes apart during daylight saving, level in winter.
- •Adelaide is one of the few major cities on a 30-minute offset.
Everything You Need to Know About PDT and ACST Time
PDT runs on Pacific Daylight Time (PDT) at UTC-07:00. ACST runs on Australian Central Standard Time (ACST) at UTC+09:30. That puts PDT 16 hours 30 minutes ahead of ACST — a difference of +16h 30m at the current offsets.
In practice, when it is 9:00 AM in PDT it is 1:30 AM in ACST on the next day. Midnight in PDT is 4:30 PM in ACST. Neither zone observes daylight saving time, so the offset between them stays constant all year.
PDT to ACST time conversion table
| PDT (PDT) | ACST (ACST) | Day |
|---|---|---|
| 12:00 AM | 4:30 PM | same day |
| 6:00 AM | 10:30 PM | same day |
| 7:00 AM | 11:30 PM | same day |
| 8:00 AM | 12:30 AM | next day |
| 9:00 AM | 1:30 AM | next day |
| 12:00 PM | 4:30 AM | next day |
| 3:00 PM | 7:30 AM | next day |
| 5:00 PM | 9:30 AM | next day |
| 6:00 PM | 10:30 AM | next day |
| 9:00 PM | 1:30 PM | next day |
Why people convert PDT to ACST time
- Scheduling a call from PDT to ACST: a 10:00 AM start in PDT lands at 2:30 AM in ACST the next day, so you can confirm the slot without doing the arithmetic yourself.
- Handling a +16h 30m gap: PDT and ACST have no overlap inside a normal 9-to-5 day, so real-time meetings need an early-morning or late-evening slot on one side. 9:00 AM in ACST is 1:30 AM in PDT.
- Watching a live event or market open: PDT viewers need 1:30 AM in ACST to catch a 9:00 AM start there, and 7:30 AM if the event is anchored to PDT.
- Always state the zone abbreviation, not just the hour. "3:00 PM PDT" is unambiguous; "3 PM" across a +16h 30m gap is not.
- With a +16h 30m gap there is no shared 9-to-5 window, so alternate the early start: one week PDT takes the early slot, the next week ACST does.
About PDT (Pacific Daylight Time)
Pacific Daylight Time (PDT) is observed from March to November on the Pacific coast. During PDT, the west coast is 7 hours behind UTC and only 2 hours behind the east coast's EDT.
About ACST (Australian Central Standard Time)
Australian Central Standard Time (ACST) is the half-hour offset of UTC+09:30 used across South Australia and the Northern Territory, taking in Adelaide and Darwin. South Australia moves to Australian Central Daylight Time (ACDT, UTC+10:30) from the first Sunday in October to the first Sunday in April, but the Northern Territory does not observe daylight saving — so Adelaide and Darwin sit 30 minutes apart in summer and level with each other in winter. The half-hour offset means Adelaide is 30 minutes behind Sydney in winter and level with it during daylight saving, which regularly catches out travellers and meeting planners.
Best time to call between PDT and ACST
With a +16h 30m offset there is no overlap inside a normal 9 AM – 5 PM day. ACST opens at 9:00 AM ACST, which is 1:30 AM in PDT, so real-time calls need an early-morning or late-evening slot on one side.
Business hours overlap
PDT and ACST have no shared working hours because of the +16h 30m gap. Teams need to alternate early starts or rely on asynchronous handovers.
PDT is 16 hours 30 minutes ahead of ACST (PDT UTC-07:00 → ACST UTC+09:30). There is no shared 9-to-5 window, so plan around an early or late slot. Remember to re-check around daylight-saving transitions.
🕐 Daylight Saving Time Info
PDT
☀ Currently in DST
Standard: UTC-08:00 · DST: UTC-07:00
Clocks fall back on Sun, Nov 1, 2026
ACST
❄ Currently in Standard Time
Standard: UTC+09:30 · DST: UTC+10:30
Clocks spring forward on Sat, Oct 3, 2026
⚠ These locations are currently in different DST states, so the time difference may change when clocks adjust.
Learn More About Time
Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:
Frequently Asked Questions
What is the time difference between PDT and ACST?
PDT (PDT, UTC-07:00) is 16 hours 30 minutes ahead of ACST (ACST, UTC+09:30). The gap is currently +16h 30m.
How do I convert PDT time to ACST time?
Add +16h 30m to PDT local time. For example, 9:00 AM in PDT is 1:30 AM in ACST (next day).
What time is it in ACST right now?
ACST uses ACST at UTC+09:30. Use the live converter at the top of this page — it updates in real time and already accounts for the +16h 30m offset from PDT.
What is the best time to call ACST from PDT?
There is no shared working-hours window because of the +16h 30m gap. The closest option is 1:00 PM in PDT, which is 5:30 AM in ACST.
Which is ahead, PDT or ACST?
PDT is 16 hours 30 minutes ahead of ACST. When it is 12:00 PM in PDT it is 4:30 AM in ACST.
Does daylight saving time affect the PDT–ACST difference?
Neither zone observes daylight saving time, so the +16h 30m offset between PDT and ACST is fixed all year.
Which other cities share PDT's time zone?
PDT also covers Los Angeles, San Francisco, Seattle, Vancouver, Portland.
Which countries use PDT, PDT's zone?
PDT is used in United States (Pacific), Canada (British Columbia), Mexico (Baja California).
Is there a day difference between PDT and ACST?
Sometimes. The +16h 30m gap is large enough that 8:00 PM or later in PDT already falls on the next day in ACST.
What is the time difference between PDT and ACST?
ACST is +16h 30m from PDT.
What timezone is PDT in?
PDT operates on its local timezone.
What timezone is ACST in?
ACST operates on its local timezone.
Which countries use PDT (Pacific Daylight Time)?
PDT is used in United States (Pacific), Canada (British Columbia), Mexico (Baja California).
Does PDT observe daylight saving time?
Yes, PDT switches to PST during summer months.
What are some interesting facts about PDT?
PDT aligns with MST at UTC-07:00. Tech company earnings calls often reference PDT/PST times.
Which cities are in the ACST timezone?
Major cities in the ACST timezone include Adelaide, Darwin, Alice Springs, Mount Gambier.
What is the UTC offset for ACST?
Australian Central Standard Time (ACST) is at UTC+09:30. During daylight saving time, it shifts to ACDT.
What should I know about the ACST timezone?
ACST uses a half-hour offset: UTC+09:30. South Australia moves to ACDT (UTC+10:30) in summer; the Northern Territory does not.
When is it midnight in PDT, what time is it in ACST?
When it is 12:00 AM (midnight) in PDT (PDT), it is +16h 30m later in ACST (ACST).
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- new york to pdt
- london to pdt
- dubai to pdt
- tokyo to pdt
- singapore to pdt
- sydney to pdt
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- delhi to pdt
- mumbai to pdt
- berlin to pdt
- hong kong to pdt
- toronto to pdt
- kathmandu to pdt
See every conversion from PDT →·See every conversion from ACST →