How many hours is CET behind ACDT?
As abbreviations, ACDT is always 9.5 hours ahead of CET: CET is UTC+1 and ACDT is UTC+10:30. To convert, add 9.5 hours.
When the CET to ACDT time difference changes
For most of the year ACDT is 7.5 hours ahead of CET. From 25 October to 31 December 2026, ACDT is 9.5 hours ahead of CET instead, because the two places change their clocks on different dates. Meetings booked by the usual gap land an hour off in those weeks.
| Dates | ACDT vs CET | Length |
|---|---|---|
| 25 October 2026 to 31 December 2026 | 9.5 hours ahead | 68 days |
| 1 January 2027 to 27 March 2027 | 9.5 hours ahead | 86 days |
| 28 March 2027 to 3 April 2027 | 8.5 hours ahead | 7 days |
| 4 April 2027 to 2 October 2027 | 7.5 hours ahead | 182 days |
| 3 October 2027 to 30 October 2027 | 8.5 hours ahead | 28 days |
| 31 October 2027 to 31 December 2027 | 9.5 hours ahead | 62 days |
Calling hours for CET and ACDT
- When ACDT is 7.5 hours ahead of CET: 1 shared office hour, 09:00 to 10:00 in CET (16:30 to 17:30 in ACDT).
- When ACDT is 9.5 hours ahead of CET: no shared 09:00 to 17:00 hours; try 08:00 in CET (17:30 in ACDT).
- When ACDT is 8.5 hours ahead of CET: no shared 09:00 to 17:00 hours; try 09:00 in CET (17:30 in ACDT).