Convert SGT to ACST
ACST is 1 hour 30 minutes ahead of SGT. SGT is UTC+8 and ACST is UTC+9:30.
Right now: SGT · ACST
Best time to schedule a meeting
Standard 9–5 working hours overlap for 7 hours: 9:00 AM–4:00 PM SGT (10:00 AM–5:00 PM ACST). Schedule meetings inside that window.
| SGT | ACST | 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 |
SGT to ACST conversion table
| SGT | ACST |
|---|---|
| 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 SGT
Singapore Time (SGT) is UTC+8. It is used in Singapore and Malaysia.
Singapore Time is UTC+8 with no daylight saving. The offset is a historical curiosity: Singapore sits at about 104°E, which is geographically UTC+7, and moved to +8 in 1982 to align with Malaysia and Hong Kong for trade. The result is that the sun is at its highest around 1pm rather than noon, and sunrise is late all year.
About ACST
Australian Central Standard Time (ACST) is UTC+9:30. It is used in Adelaide and Darwin in winter.
Australian Central Standard Time is UTC+9:30, half an hour behind the eastern states rather than a whole hour, which surprises people every time. South Australia moves to daylight saving in October and the Northern Territory does not, so Adelaide and Darwin share this offset for half the year and are an hour apart for the other half.
Does this gap change with the seasons?
Neither SGT nor ACST 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 SGT in ACST?
9:00 AM SGT is 10:30 AM ACST.
Is ACST ahead of SGT?
ACST is 1 hour 30 minutes ahead of SGT.
Which time zone does this use?
SGT is UTC+8 and ACST is UTC+9:30. 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.