GMT
Greenwich Mean Time
GMT +0
CST
Central Standard Time
GMT -6
EST
Eastern Standard Time
GMT -5

Time Difference

Greenwich Mean Time is 6 hours ahead of Central Standard Time and 5 hours ahead of Eastern Standard Time
So 8:30 pm20:30 in GMT is 2:30 pm14:30 in CST and is 3:30 pm15:30 in EST

8:30 pm20:30 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
2:30 pm14:30 Central Standard Time (CST). Offset UTC -6:00 hours
3:30 pm15:30 Eastern Standard Time (EST). Offset UTC -5:00 hours

8:30 pm20:30 GMT / 2:30 pm14:30 CST / 3:30 pm15:30 EST

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

Greenwich Mean Time

Offset: GMT is 0 hours ahead Greenwich Mean Time (GMT) and is used in Europe

Countries: It is used in following countries: Burkina Faso, Côte d'Ivoire, Britain (UK), Guernsey, Ghana, Greenland, Gambia, Guinea, Guinea-Bissau, Ireland, Isle of Man, Iceland, Jersey, Liberia, Mali, Mauritania, St Helena, Sierra Leone, Senegal, Sao Tome & Principe, Togo

Principal Cities: The largest city in the GMT timezone is London from United Kingdom with population about 7.557 million people. Other major cities in the area are Abidjan, Dakar, Grand Dakar, Accra

Greenwich Mean Time (GMT) originally referred to the mean solar time at the Royal Observatory in Greenwich, London. It is now often used to refer to Coordinated Universal Time (UTC) when this is viewed as a time zone, and in casual use for the most parts it is the same. In military GMT is known as Zulu time.Greenwich Mean Time was the same as Universal Time (UT), until the introduction of UTC in 1972 a standard astronomical concept used in many technical fields.

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

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • Z - is the zone designator for the zero UTC/GMT offset, also known as 'Zulu' time
  • +00 - basic short
  • +0000 - basic
  • +00:00 - extended

Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0000 - sign character (+) followed by a four digit time providing hours (00) and minutes (00) of the offset. Indicates zero hour and zero minutes time differences of the zero meridian.

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

IANA/Olson: Reflects GMT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Africa/Abidjan
  • Africa/Accra
  • Africa/Bamako
  • Africa/Banjul
  • Africa/Bissau
  • Africa/Conakry
  • Africa/Dakar
  • Africa/Freetown
  • Africa/Lome
  • Africa/Monrovia
  • Africa/Nouakchott
  • Africa/Ouagadougou
  • Africa/Sao_Tome
  • Africa/Timbuktu
  • America/Danmarkshavn
  • Atlantic/Reykjavik
  • Atlantic/St_Helena
  • Eire
  • Etc/GMT
  • Etc/GMT+0
  • Etc/GMT-0
  • Etc/GMT0
  • Etc/Greenwich
  • Europe/Belfast
  • Europe/Dublin
  • Europe/Guernsey
  • Europe/Isle_of_Man
  • Europe/Jersey
  • Europe/London
  • GB
  • GB-Eire
  • GMT
  • GMT+0
  • GMT-0
  • GMT0
  • Greenwich
  • Iceland

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

  • Greenwich Mean Time - UTC +0
  • GMT+08:00 - UTC +8
  • GMT-03:00 - UTC -3
  • GMT+10:00 - UTC +10
  • GMT+03:00 - UTC +3
  • GMT - UTC +1
  • GMT+04:00 - UTC +4
  • GMT-01:00 - UTC -1

Time zones with the GMT +0 offset:

  • EGST - Eastern Greenland Summer Time
  • GMT - Greenwich Mean Time
  • WET - Western European Time
  • AZOST - Azores Summer Time
  • UTC - Universal Time Coordinated
  • WT - Western Sahara Standard Time
  • Z - Zulu Time Zone
  • +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 -


Eastern Standard Time

Offset: EST is 5 hours behind Greenwich Mean Time (GMT) and is used in North America

Countries: It is used in following countries: Bahamas, Canada, Haiti, Jamaica, Cayman Islands, Mexico, Panama, Turks & Caicos Is, United States

Principal Cities: The largest city in the EST timezone is New York City from USA with population about 8.175 million people. Other major cities in the area are Toronto, Montreal, Brooklyn, Borough of Queens

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 Eastern Daylight Time (EDT).

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

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

French: HNE - Heure Normale de l'Est

Spanish: ET - Tiempo del Este, ET - Zona Sureste

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

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -05 - basic short
  • -0500 - basic
  • -05:00 - extended

Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0500 - sign character (-) followed by a four digit time providing hours (05) and minutes (00) of the offset. Indicates five 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
  • Romeo - Military abbreviation for EST
  • R - short form of 'Romeo'

IANA/Olson: Reflects EST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Atikokan
  • America/Cancun
  • America/Cayman
  • America/Coral_Harbour
  • America/Detroit
  • America/Fort_Wayne
  • America/Grand_Turk
  • America/Indiana/Indianapolis
  • America/Indiana/Marengo
  • America/Indiana/Petersburg
  • America/Indiana/Vevay
  • America/Indiana/Vincennes
  • America/Indiana/Winamac
  • America/Indianapolis
  • America/Iqaluit
  • America/Jamaica
  • America/Kentucky/Louisville
  • America/Kentucky/Monticello
  • America/Louisville
  • America/Montreal
  • America/Nassau
  • America/New_York
  • America/Nipigon
  • America/Panama
  • America/Pangnirtung
  • America/Port-au-Prince
  • America/Thunder_Bay
  • America/Toronto
  • Canada/Eastern
  • EST
  • EST5EDT
  • Jamaica
  • US/East-Indiana
  • US/Eastern
  • US/Michigan

Time zones with the GMT -5 offset:

  • CDT - Central Daylight Time
  • EST - Eastern Standard Time
  • ET - Eastern Time
  • COT - Colombia Time
  • CST - Cuba Standard Time
  • EASST - Easter Island Summer Time
  • ECT - Ecuador Time
  • PET - Peru Time
  • R - Romeo Time Zone
  • -05 -