AST to CST Converter
Time Difference
Atlantic Daylight Time is 2 hours ahead of Central Daylight Time
6:30 pm18:30 in ADT is 4:30 pm16:30 in CDT
AST to CST call time
Best time for a conference call or a meeting is between 10am-6pm in AST which corresponds to 8am-4pm in CST
6:30 pm18:30 Atlantic Daylight Time (ADT). Offset UTC -3:00 hours
4:30 pm16:30 Central Daylight Time (CDT). Offset UTC -5:00 hours
6:30 pm18:30 ADT / 4:30 pm16:30 CDT
| ADT | CDT |
|---|---|
| 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 |
| 0:00 | 22:00 |
| 1:00 | 23:00 |
| 2:00 | 0:00 |
| 3:00 | 1:00 |
| 4:00 | 2:00 |
| 5:00 | 3:00 |
| 6:00 | 4:00 |
| 7:00 | 5:00 |
| 8:00 | 6:00 |
| 9:00 | 7:00 |
| 10:00 | 8:00 |
| 11:00 | 9:00 |
| 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: It is used in following countries: 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 timezone is Santo Domingo from Dominican Republic with population about 2.202 million people. Other major cities in the area are 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, however during summer some places switch clocks for one hour forward when daylight saving comes into effect and observe Atlantic Daylight Time (ADT).
End: Atlantic Standard Time (AST) has ended on Sunday, March 9, 2025 at 2:00 am local time and clocks were set one hour forward to Sunday, March 9, 2025, 3:00 am local daylight time instead. Standard time ends annually the on second Sunday of March.
Start: Atlantic Standard Time (AST) starts on Sunday, November 2, 2025 at 2:00 am local time and clocks are set one hour back to Sunday, November 2, 2025, 1:00 am. Standard time starts annually the on first Sunday of November.
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 four hour and zero minutes time differences 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
- Azerbaijan Standard Time - UTC +4
- Argentina Standard Time - UTC -3
- Azores Summer Time - UTC +0
- Apia Standard Time - UTC +13
- 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 Standard Time
Offset: CST is 6 hours behind Greenwich Mean Time (GMT) and is used in North America
Countries: It is used in following countries: Belize, Canada, Costa Rica, Guatemala, Honduras, Mexico, Nicaragua, El Salvador, United States
Principal Cities: The largest city in the CST timezone is Mexico City from Mexico with population about 12.294 million people. Other major cities in the area are Chicago, Houston, Iztapalapa, Ecatepec
French: HNC - Heure Normale du Centre
Spanish: CT - Tiempo Central Estándar, CT - Zona Centro
Daylight Saving: This is a standard time zone, however during summer some places switch clocks for one hour forward when daylight saving comes into effect and observe Central Daylight Time (CDT).
End: Central Standard Time (CST) has ended on Sunday, March 9, 2025 at 2:00 am local time and clocks were set one hour forward to Sunday, March 9, 2025, 3:00 am local daylight time instead. Standard time ends annually the on second Sunday of March.
Start: Central Standard Time (CST) starts on Sunday, November 2, 2025 at 2:00 am local time and clocks are set one hour back to Sunday, November 2, 2025, 1:00 am. Standard time starts annually the on first Sunday of November.
CST 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 six hour and zero minutes time differences to the west of the zero meridian.
- Sierra - Military abbreviation for CST
- S - short form of 'Sierra'
- America/Bahia_Banderas
- America/Belize
- America/Chicago
- America/Chihuahua
- America/Costa_Rica
- America/El_Salvador
- America/Guatemala
- America/Indiana/Knox
- America/Indiana/Tell_City
- America/Knox_IN
- America/Managua
- America/Matamoros
- America/Menominee
- America/Merida
- America/Mexico_City
- America/Monterrey
- America/North_Dakota/Beulah
- America/North_Dakota/Center
- America/North_Dakota/New_Salem
- America/Ojinaga
- America/Rainy_River
- America/Rankin_Inlet
- America/Regina
- America/Resolute
- America/Swift_Current
- America/Tegucigalpa
- America/Winnipeg
- CST6CDT
- Canada/Central
- Canada/Saskatchewan
- Mexico/General
- US/Central
- US/Indiana-Starke
- Central Standard Time - UTC -6
- China Standard Time - UTC +8
- Cuba Standard Time - UTC -5
- Colombia Standard Time - UTC -5
- CST - Central Standard Time
- CT - Central Time
- MDT - Mountain Daylight Time
- EAST - Easter Island Standard Time
- GALT - Galapagos Time
- S - Sierra Time Zone