CST
Central Standard Time
GMT -6
AST/ADT
Atlantic Standard Time
GMT -4
ADT automatically adjusted to AST time zone, that is in use

Time Difference

Central Standard Time is 2 hours behind of Atlantic Standard Time
So 8:30 am08:30 in CST is 10:30 am10:30 in AST

8:30 am08:30 Central Standard Time (CST). Offset UTC -6:00 hours
10:30 am10:30 Atlantic Standard Time (AST). Offset UTC -4:00 hours

8:30 am08:30 CST / 10:30 am10:30 AST

CST AST
12am (midnight) 2am
1am 3am
2am 4am
3am 5am
4am 6am
5am 7am
6am 8am
7am 9am
8am 10am
9am 11am
10am 12pm (noon)
11am 1pm
12pm (noon) 2pm
1pm 3pm
2pm 4pm
3pm 5pm
4pm 6pm
5pm 7pm
6pm 8pm
7pm 9pm
8pm 10pm
9pm 11pm
10pm 12am (midnight)
11pm 1am
0:00 2:00
1:00 3:00
2:00 4:00
3:00 5:00
4:00 6:00
5:00 7:00
6:00 8:00
7:00 9:00
8:00 10:00
9:00 11:00
10:00 12:00
11:00 13:00
12:00 14:00
13:00 15:00
14:00 16:00
15:00 17:00
16:00 18:00
17:00 19:00
18:00 20:00
19:00 21:00
20:00 22:00
21:00 23:00
22:00 0:00
23:00 1:00

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

Daylight Saving: This is a standard timezone, however during summer some places switch clocks for one hour forward when daylight saving comes into effect and observe Central Daylight Time (CDT).

Start: CST started and clocks were set one hour back on Sunday, 01 November 2020, at 2:00 (2:00 am) local time.

End: CST ends and clocks are set one hour forward on Sunday, 14 March 2021, at 2:00 (2:00 am) local time.

French: HNC - Heure Normale du Centre

Spanish: CT - Tiempo Central Estándar, CT - Zona Centro

CST Time Zone Geo Map
CST timezone map
CST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -06 - basic short
  • -0600 - basic
  • -06:00 - extended

Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -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.

Military/NATO: Used by the U.S. military, Chinese military and others
  • Sierra - Military abbreviation for CST
  • S - short form of 'Sierra'

IANA/Olson: Reflects CST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Bahia_Banderas
  • America/Belize
  • America/Chicago
  • 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/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

CST Abbreviation: Several time zones share CST abbreviation and it could refer to these time zones

  • Central Standard Time - UTC -6
  • China Standard Time - UTC +8
  • Cuba Standard Time - UTC -5

Time zones with the GMT -6 offset:

  • CST - Central Standard Time
  • CT - Central Time
  • MDT - Mountain Daylight Time
  • EAST - Easter Island Standard Time
  • GALT - Galapagos Time
  • S - Sierra Time Zone
  • -06 -


Atlantic Daylight Time

Offset: ADT is 3 hours behind Greenwich Mean Time (GMT) and is used in North America

Countries: It is used in following countries: Bermuda, Canada, Greenland

Principal Cities: The largest city in the ADT timezone is Halifax from Canada with population about 359,111 people. Other major cities in the area are Sydney, Dartmouth, Saint John, Moncton

Daylight Saving: Atlantic Daylight Time (ADT) is a daylight saving/summer timezone, however during winter some places adjust time for one hour back and observe Atlantic Standard Time (AST).

End: ADT ended and clocks were set one hour back on Sunday, 01 November 2020, at 2:00 (2:00 am) local time.

Start: ADT starts and clocks are set one hour forward on Sunday, 14 March 2021, at 2:00 (2:00 am) local time.

French: HAA - Heure Avancée de l'Atlantique

ADT Time Zone Geo Map
ADT timezone map
ADT representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -03 - basic short
  • -0300 - basic
  • -03:00 - extended

Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0300 - sign character (-) followed by a four digit time providing hours (03) and minutes (00) of the offset. Indicates three hour and zero minutes time differences to the west of the zero meridian.

Military/NATO: Used by the U.S. military, Chinese military and others
  • Papa - Military abbreviation for ADT
  • P - short form of 'Papa'

IANA/Olson: Reflects ADT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Glace_Bay
  • America/Goose_Bay
  • America/Halifax
  • America/Moncton
  • America/Thule
  • Atlantic/Bermuda
  • Canada/Atlantic

Time zones with the GMT -3 offset:

  • ADT - Atlantic Daylight Time
  • PMT - Pierre & Miquelon Standard Time
  • PMST - Pierre & Miquelon Standard Time
  • WGT - West Greenland Time
  • AMST - Amazon Summer Time
  • ART - Argentina Time
  • BRT - Brasília time
  • CLST - Chile Summer Time
  • FKST - Falkland Islands Summer Time
  • GFT - French Guiana Time
  • P - Papa Time Zone
  • PYST - Paraguay Summer Time
  • SRT - Suriname Time
  • UYT - Uruguay Time
  • GMT - GMT-03:00
  • -03 -