Convert JST to ACDT
ACDT is 1 hour 30 minutes ahead of JST. JST is UTC+9 and ACDT is UTC+10:30.
Right now: JST · ACDT
Best time to schedule a meeting
Standard 9–5 working hours overlap for 7 hours: 9:00 AM–4:00 PM JST (10:00 AM–5:00 PM ACDT). Schedule meetings inside that window.
| JST | ACDT | 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 |
JST to ACDT conversion table
| JST | ACDT |
|---|---|
| 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 JST
Japan Standard Time (JST) is UTC+9. It is used in all of Japan, with no daylight saving.
Japan Standard Time is UTC+9 for the whole country and has had no daylight saving since 1951, when the occupation-era experiment was abandoned. Proposals to reintroduce it, most recently before the 2020 Olympics, have failed each time. The offset is shared with South Korea, so Tokyo and Seoul never differ by even a minute.
About ACDT
Australian Central Daylight Time (ACDT) is UTC+10:30. It is used in Adelaide in summer.
Australian Central Daylight Time is UTC+10:30, what South Australia keeps from October to April. Darwin stays on ACST through the summer, so for those months two cities in the same nominal zone are an hour apart — the only reason to be precise about which of the two abbreviations a meeting invitation carries.
Does this gap change with the seasons?
Neither JST nor ACDT shifts with the seasons, so this 1.5-hour difference holds all year. That is unusual enough to be worth relying on: most cross-continental gaps move twice a year.
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 JST in ACDT?
9:00 AM JST is 10:30 AM ACDT.
Is ACDT ahead of JST?
ACDT is 1 hour 30 minutes ahead of JST.
Which time zone does this use?
JST is UTC+9 and ACDT is UTC+10:30. 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.