CDT/CST
Central Daylight Time
GMT -5
CST automatically adjusted to CDT time zone, that is in use
IRST
Iran Standard Time
GMT +3:30

Time Difference

Central Daylight Time is 8 hours and 30 minutes behind Iran Standard Time
10:00 am10:00 in CDT is 6:30 pm18:30 in IRST

CST to IRST call time
Best time for a conference call or a meeting is between 8am-10am in CST which corresponds to 5:30pm-7:30pm in IRST

10:00 am10:00 Central Daylight Time (CDT). Offset UTC -5:00 hours
6:30 pm18:30 Iran Standard Time (IRST). Offset UTC +3:30 hours

10:00 am10:00 CDT / 6:30 pm18:30 IRST

CDT IRST
12am (midnight) 8:30 am
1am 9:30 am
2am 10:30 am
3am 11:30 am
4am 12:30 pm
5am 1:30 pm
6am 2:30 pm
7am 3:30 pm
8am 4:30 pm
9am 5:30 pm
10am 6:30 pm
11am 7:30 pm
12pm (noon) 8:30 pm
1pm 9:30 pm
2pm 10:30 pm
3pm 11:30 pm
4pm 12:30 am
5pm 1:30 am
6pm 2:30 am
7pm 3:30 am
8pm 4:30 am
9pm 5:30 am
10pm 6:30 am
11pm 7:30 am
0:00 8:30
1:00 9:30
2:00 10:30
3:00 11:30
4:00 12:30
5:00 13:30
6:00 14:30
7:00 15:30
8:00 16:30
9:00 17:30
10:00 18:30
11:00 19:30
12:00 20:30
13:00 21:30
14:00 22:30
15:00 23:30
16:00 0:30
17:00 1:30
18:00 2:30
19:00 3:30
20:00 4:30
21:00 5:30
22:00 6:30
23:00 7:30

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

CST Time Zone Geo Map
CST timezone map

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).

Daylight saving time clock moves forward for one hour from 2am to 3amEnd: Central Standard Time (CST) has ended on Sunday, March 10, 2024 at 2:00 am local time and clocks were set one hour forward to Sunday, March 10, 2024, 3:00 am local daylight time instead. Standard time ends annually the on second Sunday of March.

Daylight saving time clock moves back for one hour from 2am to 1amStart: Central Standard Time (CST) starts on Sunday, November 3, 2024 at 2:00 am local time and clocks are set one hour back to Sunday, November 3, 2024, 1:00 am. Standard time starts annually the on first Sunday of November.

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/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
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

Iran Standard Time

Offset: IRST is 3 hours and 30 minutes ahead Greenwich Mean Time (GMT) and is used in Asia

IRST Time Zone Geo Map
IRST timezone map

IRST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +0330 - basic
  • +03:30 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0330 - sign character (+) followed by a four digit time providing hours (03) and minutes (30) of the offset. Indicates three hour and thirty minutes time differences to the east of the zero meridian.