Observatory log
Chicago and Colac, compared
- 01Difference now
Colac is 16 hours ahead of Chicago.
Chicago: CDT (UTC−5) · Colac: AEDT (UTC+11)
Next changeFrom 1 November 2026: Colac is 17 hours ahead of Chicago.
- 02Through 2026–2027
- 1 January 2026 – 8 March 2026+17 h
- 8 March 2026 – 5 April 2026+16 h
- 5 April 2026 – 4 October 2026+15 h
- 4 October 2026 – 1 November 2026+16 h
- 1 November 2026 – 14 March 2027+17 h
- 14 March 2027 – 4 April 2027+16 h
- 4 April 2027 – 3 October 2027+15 h
- 3 October 2027 – 7 November 2027+16 h
- 7 November 2027 – 31 December 2027+17 h
Difference of Colac from Chicago. It changes on the days either place changes its clocks (dates local to that place).
- 03Shared working hours
Their working days never overlap.
Counted as 09:00–17:00 local time on each place’s own working days, for the next seven days.
- 04Best time to meet
14:00–22:00 in Chicago = 06:00–14:00 in Colac
No shared office hours: this is early or late for one side (Mon–Thu).
- 05Weekend
Chicago: Saturday and Sunday
Colac: Saturday and Sunday
24 hours
A day in Chicago, in Colac
| Chicago | Colac | Working hours, evening, night or weekend in each place |
|---|---|---|
| 00:00 | 16:00 | |
| 01:00 | 17:00 | |
| 02:00 | 18:00 | |
| 03:00 | 19:00 | |
| 04:00 | 20:00 | |
| 05:00 | 21:00 | |
| 06:00 | 22:00 | |
| 07:00 | 23:00 | |
| 08:00 | 00:00Tomorrow | |
| 09:00 | 01:00Tomorrow | |
| 10:00 | 02:00Tomorrow | |
| 11:00 | 03:00Tomorrow | |
| 12:00 | 04:00Tomorrow | |
| 13:00 | 05:00Tomorrow | |
| 14:00 | 06:00Tomorrow | |
| 15:00 | 07:00Tomorrow | |
| 16:00 | 08:00Tomorrow | |
| 17:00 | 09:00Tomorrow | |
| 18:00 | 10:00Tomorrow | |
| 19:00 | 11:00Tomorrow | |
| 20:00 | 12:00Tomorrow | |
| 21:00 | 13:00Tomorrow | |
| 22:00 | 14:00Tomorrow | |
| 23:00 | 15:00Tomorrow |
Working hoursEarly or eveningNightWeekend
Plan a meeting: Chicago and Colac
More time differences with Chicago
Questions
Asked about Chicago and Colac
What is the time difference between Chicago and Colac?
Colac is 16 hours ahead of Chicago. This holds until 1 November 2026; then Colac is 17 hours ahead of Chicago.
What is the best time for a call between Chicago and Colac?
No shared office hours. The least awkward windows, early or late for one side: Mon–Thu: 14:00–22:00 in Chicago = 06:00–14:00 in Colac (tomorrow) · 8 h.
When does the time difference between Chicago and Colac change?
In the next 12 months it changes on: 1 November 2026 (+17 h); 14 March 2027 (+16 h); 4 April 2027 (+15 h); 3 October 2027 (+16 h).