Observatory log
Chicago and Cao Lanh, compared
- 01Difference now
Cao Lanh is 12 hours ahead of Chicago.
Chicago: CDT (UTC−5) · Cao Lanh: UTC+7 (UTC+7)
Next changeFrom 1 November 2026: Cao Lanh is 13 hours ahead of Chicago.
- 02Through 2026–2027
- 1 January 2026 – 8 March 2026+13 h
- 8 March 2026 – 1 November 2026+12 h
- 1 November 2026 – 14 March 2027+13 h
- 14 March 2027 – 7 November 2027+12 h
- 7 November 2027 – 31 December 2027+13 h
Difference of Cao Lanh 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
09:00–10:00 in Chicago = 21:00–22:00 in Cao Lanh
No shared office hours: this is early or late for one side (Mon–Fri).
Also possible: Mon–Thu: 21:00–22:00 in Chicago = 09:00–10:00 in Cao Lanh (tomorrow) · 1 h.
- 05Weekend
Chicago: Saturday and Sunday
Cao Lanh: Saturday and Sunday
24 hours
A day in Chicago, in Cao Lanh
| Chicago | Cao Lanh | Working hours, evening, night or weekend in each place |
|---|---|---|
| 00:00 | 12:00 | |
| 01:00 | 13:00 | |
| 02:00 | 14:00 | |
| 03:00 | 15:00 | |
| 04:00 | 16:00 | |
| 05:00 | 17:00 | |
| 06:00 | 18:00 | |
| 07:00 | 19:00 | |
| 08:00 | 20:00 | |
| 09:00 | 21:00 | |
| 10:00 | 22:00 | |
| 11:00 | 23:00 | |
| 12:00 | 00:00Tomorrow | |
| 13:00 | 01:00Tomorrow | |
| 14:00 | 02:00Tomorrow | |
| 15:00 | 03:00Tomorrow | |
| 16:00 | 04:00Tomorrow | |
| 17:00 | 05:00Tomorrow | |
| 18:00 | 06:00Tomorrow | |
| 19:00 | 07:00Tomorrow | |
| 20:00 | 08:00Tomorrow | |
| 21:00 | 09:00Tomorrow | |
| 22:00 | 10:00Tomorrow | |
| 23:00 | 11:00Tomorrow |
Working hoursEarly or eveningNightWeekend
Plan a meeting: Chicago and Cao Lanh
More time differences with Chicago
Questions
Asked about Chicago and Cao Lanh
What is the time difference between Chicago and Cao Lanh?
Cao Lanh is 12 hours ahead of Chicago. This holds until 1 November 2026; then Cao Lanh is 13 hours ahead of Chicago.
What is the best time for a call between Chicago and Cao Lanh?
No shared office hours. The least awkward windows, early or late for one side: Mon–Fri: 09:00–10:00 in Chicago = 21:00–22:00 in Cao Lanh · 1 h; Mon–Thu: 21:00–22:00 in Chicago = 09:00–10:00 in Cao Lanh (tomorrow) · 1 h.
When does the time difference between Chicago and Cao Lanh change?
In the next 12 months it changes on: 1 November 2026 (+13 h); 14 March 2027 (+12 h).