AST to CT Converter
Quick answers
For most of the year, ADT is 2 hours ahead of CT. During seasonal clock changes, AST is 2 hours ahead of CT. Briefly around those changes, ADT is 3 hours ahead of CT or AST is 1 hour ahead of CT.
For most of the year, working hours of 9:00 am to 5:00 pm in ADT correspond to 7:00 am to 3:00 pm in CT. During seasonal clock changes, working hours of 9:00 am to 5:00 pm in AST correspond to 7:00 am to 3:00 pm in CT.
Compare AST time with CT time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Atlantic Standard Time is 2 hours ahead of Central Time
8:00 am08:00 in AST is 6:00 am06:00 in CT
AST to CT call time
Best time for a conference call or a meeting is between 11am-5pm in AST which corresponds to 9am-3pm in CT
8:00 am08:00 Atlantic Standard Time (AST). Offset UTC -4:00 hours
6:00 am06:00 Central Time (CT). Offset UTC -6:00 hours
8:00 am08:00 AST / 6:00 am06:00 CT
| AST | CT |
|---|---|
| 12am (midnight) | 10pm |
| 1am | 11pm |
| 2am | 12am (midnight) |
| 3am | 1am |
| 4am | 2am |
| 5am | 3am |
| 6am | 4am |
| 7am | 5am |
| 8am | 6am |
| 9am | 7am |
| 10am | 8am |
| 11am | 9am |
| 12pm (noon) | 10am |
| 1pm | 11am |
| 2pm | 12pm (noon) |
| 3pm | 1pm |
| 4pm | 2pm |
| 5pm | 3pm |
| 6pm | 4pm |
| 7pm | 5pm |
| 8pm | 6pm |
| 9pm | 7pm |
| 10pm | 8pm |
| 11pm | 9pm |
| 00:00 | 22:00 |
| 01:00 | 23:00 |
| 02:00 | 00:00 |
| 03:00 | 01:00 |
| 04:00 | 02:00 |
| 05:00 | 03:00 |
| 06:00 | 04:00 |
| 07:00 | 05:00 |
| 08:00 | 06:00 |
| 09:00 | 07:00 |
| 10:00 | 08:00 |
| 11:00 | 09:00 |
| 12:00 | 10:00 |
| 13:00 | 11:00 |
| 14:00 | 12:00 |
| 15:00 | 13:00 |
| 16:00 | 14:00 |
| 17:00 | 15:00 |
| 18:00 | 16:00 |
| 19:00 | 17:00 |
| 20:00 | 18:00 |
| 21:00 | 19:00 |
| 22:00 | 20:00 |
| 23:00 | 21:00 |
Atlantic Standard Time
Offset: AST is 4 hours behind Greenwich Mean Time (GMT) and is used in North America
Countries using this time zone: Antigua & Barbuda, Anguilla, Aruba, Barbados, St Barthelemy, Bermuda, Caribbean NL, Canada, Curaçao, Dominica, Dominican Republic, Grenada, Greenland, Guadeloupe, St Kitts & Nevis, St Lucia, St Martin (French), Martinique, Montserrat, Puerto Rico, St Maarten (Dutch), Trinidad & Tobago, St Vincent, Virgin Islands (UK), Virgin Islands (US)
Principal Cities: The largest city in the AST time zone is Santo Domingo in Dominican Republic, with about 2.202 million people. Other major cities in this time zone include Santiago de los Caballeros, Santo Domingo Oeste, San Juan, Halifax.
French: HNA - Heure Normale de l'Atlantique
Spanish: AST - Tiempo Estándar del Atlántico
Daylight Saving: This is a standard time zone. During summer, some places set clocks forward one hour for daylight saving time and observe Atlantic Daylight Time (ADT).
Start: Atlantic Standard Time (AST) started on Sunday, November 2, 2025 at 2:00 am local time and clocks were set one hour back to Sunday, November 2, 2025, 1:00 am. Standard time starts annually on the first Sunday of November.
End: Atlantic Standard Time (AST) ends on Sunday, March 8, 2026 at 2:00 am local time and clocks are set one hour forward to Sunday, March 8, 2026, 3:00 am local daylight time instead. Standard time ends annually on the second Sunday of March.
AST representations, usage and related time zones
- -04 - basic short
- -0400 - basic
- -04:00 - extended
- -0400 - sign character (-) followed by a four digit time providing hours (04) and minutes (00) of the offset. Indicates an offset of four hours to the west of the zero meridian.
- Quebec - Military abbreviation for AST
- Q - short form of 'Quebec'
- America/Anguilla
- America/Antigua
- America/Aruba
- America/Barbados
- America/Blanc-Sablon
- America/Curacao
- America/Dominica
- America/Glace_Bay
- America/Goose_Bay
- America/Grenada
- America/Guadeloupe
- America/Halifax
- America/Kralendijk
- America/Lower_Princes
- America/Marigot
- America/Martinique
- America/Moncton
- America/Montserrat
- America/Port_of_Spain
- America/Puerto_Rico
- America/Santo_Domingo
- America/St_Barthelemy
- America/St_Kitts
- America/St_Lucia
- America/St_Thomas
- America/St_Vincent
- America/Thule
- America/Tortola
- America/Virgin
- Atlantic/Bermuda
- Canada/Atlantic
- Atlantic Standard Time - UTC -4
- Arabia Standard Time - UTC +3
- AST - Atlantic Standard Time
- EDT - Eastern Daylight Time
- AMT - Amazon Time
- BOT - Bolivia Time
- CDT - Cuba Daylight Time
- CLT - Chile Standard Time
- FKT - Falkland Island Time
- GYT - Guyana Time
- HLV - Hora Legal de Venezuela
- PYT - Paraguay Time
- Q - Quebec Time Zone
- VET - Venezuelan Standard Time
Central Time
Central Time (CT) is a general term used to describe the areas that observe either the Central Standard Time (CST) or Central Daylight Time (CDT) in the United States and Canada. CT is not static but switches between CDT and CST.
Territories observing the time zone are primarily in North and Central America. It runs through several Mexican and U.S. states, as well as several Canadian provinces and Central American countries.
Countries using this time zone: Belize, Canada, Costa Rica, Guatemala, Honduras, Mexico, Nicaragua, El Salvador, United States.
Principal Cities: The largest city in the CST time zone is Mexico City in Mexico, with about 12.294 million people. Other major cities in this time zone include Chicago, Houston, Iztapalapa, Ecatepec.
French: HNC - Heure Normale du Centre
Spanish: CT - Tiempo Central Estándar, CT - Zona Centro
CT representations, usage and related time zones
- -06 - basic short
- -0600 - basic
- -06:00 - extended
- -0600 - sign character (-) followed by a four digit time providing hours (06) and minutes (00) of the offset. Indicates an offset of six hours to the west of the zero meridian.
- Sierra - Military abbreviation for CT
- S - short form of 'Sierra'
- CST - Central Standard Time
- CT - Central Time
- MDT - Mountain Daylight Time
- EAST - Easter Island Standard Time
- GALT - Galapagos Time
- S - Sierra Time Zone