AST to CDT
-2hAST
ASTSOURCECDT
CDTGreen rows indicate typical business hours (9 AM - 5 PM)
AST and CDT on the World Map
The map below highlights the AST (Atlantic Standard Time) and CDT (Central Daylight Time) timezone regions across the globe.
AST – Atlantic Standard Time
UTC-04:00Atlantic Standard Time (AST) is the time zone for the Canadian Atlantic provinces and the Caribbean, 4 hours behind UTC.
- •Puerto Rico uses AST year-round and does not observe DST.
- •AST is 1 hour ahead of EST.
- •Halifax, the capital of Nova Scotia, is the largest city in AST Canada.
CDT – Central Daylight Time
UTC-05:00Central Daylight Time (CDT) is the daylight saving offset in the Central Time Zone, 5 hours behind UTC.
- •CDT is the same offset as EST (UTC-05:00), which can cause confusion.
- •CDT runs from the second Sunday in March to the first Sunday in November.
Comparing Time Zones: AST and CDT
AST (Atlantic Standard Time) operates on the Atlantic Standard Time (UTC-04:00). CDT (Central Daylight Time) uses Central Daylight Time (UTC-05:00).
The time difference between AST and CDT is 120 minutes (+2h). When it's noon in AST, it's 10:00 AM in CDT.
Why Convert AST to CDT Time?
Whether you're traveling from AST to CDT or simply need to coordinate across time zones, understanding the 2-hour difference is key. Use this converter to quickly determine the current time in CDT and ensure your schedule aligns perfectly.
Best Practice: When proposing meeting times to someone in CDT, offer a few options in their local time to show consideration for the 2-hour difference.
About AST (Atlantic Standard Time)
Atlantic Standard Time (AST) covers Canada's Atlantic provinces (Nova Scotia, New Brunswick, Prince Edward Island, and most of Labrador), as well as several Caribbean nations. Puerto Rico and the US Virgin Islands use AST year-round without daylight saving time. The Canadian provinces switch to Atlantic Daylight Time (ADT) in summer.
About CDT (Central Daylight Time)
Central Daylight Time (CDT) is observed during summer months in the US and Canadian portions of the Central Time Zone. Clocks are moved forward by one hour, aligning with Eastern Standard Time (EST). Most of Mexico and Central America do not observe CDT, staying on CST year-round.
Best Time to Call Between AST and CDT
If you want to reach someone in CDT during standard business hours (9 AM – 5 PM CDT), the best time to call from AST would be:
- CDT 9:00 AM = AST 11:00 AM
- CDT 12:00 PM = AST 02:00 PM
- CDT 5:00 PM = AST 07:00 PM
Business Hours Overlap
AST and CDT have a significant business hours overlap (6 hours), making real-time collaboration easy during standard working hours.
To wrap up, keeping track of the -2h gap between AST and CDT is essential for seamless communication. Bookmark this converter to stay on top of your schedule.
🕐 Daylight Saving Time Info
AST
☀ Currently in DST
Standard: UTC-04:00 · DST: UTC-03:00
Clocks fall back on Sun, Nov 1, 2026
CDT
☀ Currently in DST
Standard: UTC-06:00 · DST: UTC-05:00
Clocks fall back on Sun, Nov 1, 2026
Learn More About Time
Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:
Frequently Asked Questions
What is the time difference between AST and CDT?
CDT is -2h from AST.
What timezone is AST in?
AST operates on its local timezone.
What timezone is CDT in?
CDT operates on its local timezone.
Which countries use AST (Atlantic Standard Time)?
AST is used in Canada (Atlantic provinces), Puerto Rico, US Virgin Islands, Dominican Republic, Venezuela, Bolivia, and 2 more countries.
Does AST observe daylight saving time?
Yes, AST switches to ADT during summer months.
What are some interesting facts about AST?
Puerto Rico uses AST year-round and does not observe DST. AST is 1 hour ahead of EST.
Which cities are in the CDT timezone?
Major cities in the CDT timezone include Chicago, Houston, Dallas, Austin, Winnipeg, Nashville.
What is the UTC offset for CDT?
Central Daylight Time (CDT) is at UTC-05:00. During daylight saving time, it shifts to CST.
What should I know about the CDT timezone?
CDT is the same offset as EST (UTC-05:00), which can cause confusion. CDT runs from the second Sunday in March to the first Sunday in November.
When is it midnight in AST, what time is it in CDT?
When it is 12:00 AM (midnight) in AST (AST), it is -2h later in CDT (CDT).
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