IST
Irish Standard Time
GMT +1
CDT/CST
Central Daylight Time
GMT -5
CST automatically adjusted to CDT time zone, that is in use

Time Difference

Irish Standard Time is 6 hours ahead of Central Daylight Time
1:00 am01:00 in IST is 7:00 pm19:00 in CDT

IST to CST call time
Best time for a conference call or a meeting is between 3pm-6pm in IST which corresponds to 8am-11am in CST

1:00 am01:00 Irish Standard Time (IST). Offset UTC +1:00 hour
7:00 pm19:00 Central Daylight Time (CDT). Offset UTC -5:00 hours

1:00 am01:00 IST / 7:00 pm19:00 CDT

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

Irish Standard Time

Offset: IST is 1 hour ahead Greenwich Mean Time (GMT) and is used in Europe

Countries: It is used in following countries: Ireland

Principal Cities: The largest city in the IST timezone is Dublin from Ireland with population about 1.024 million people. Other major cities in the area are Cork, Dun Laoghaire, Luimneach, Gaillimh

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 Greenwich Mean Time (GMT).

Start: IST starts annually on the same date and time. and clocks were set one hour back on Sunday, 28 March 2021, at 3:00 (3:00 am) local time.

End: IST ends annually on the same date and time. and clocks are set one hour forward on Sunday, 31 October 2021, at 2:00 (2:00 am) local time.

IST Time Zone Geo Map
IST timezone map

IST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +01 - basic short
  • +0100 - basic
  • +01:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0100 - sign character (+) followed by a four digit time providing hours (01) and minutes (00) of the offset. Indicates one hour and zero minutes time differences to the east of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Alpha - Military abbreviation for IST
  • A - short form of 'Alpha'
IANA/Olson: Reflects IST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Eire
  • Europe/Dublin
IST Abbreviation: Several time zones share IST abbreviation and it could refer to these time zones
  • India Standard Time - UTC +5:30
  • Irish Standard Time - UTC +1
  • Israel Standard Time - UTC +2
  • Iran Standard Time - UTC +3:30
Time zones with the GMT +1 offset:
  • BST - British Summer Time
  • CET - Central European Time
  • IST - Irish Standard Time
  • WEST - Western European Summer Time
  • A - Alpha Time Zone
  • CET - Central European Time
  • MEZ - Mitteleuropäische Zeit
  • WAT - West Africa Time
  • WST - Western Sahara Summer Time
  • BMT - Biel Mean Time
  • GMT - GMT
  • +01 -

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 adjust time for one hour forward for daylight saving and observe Central Daylight Time (CDT).

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

Start: CST starts annually on the same date and time. and clocks are set one hour back on Sunday, 07 November 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
  • Colombia 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
  • GT - Galapagos Time