CDT
Central Daylight Time
GMT -5
12am
3am
6am
9am
12pm
3pm
6pm
9pm
AEST
Australian Eastern Standard Time
GMT +10
12am
3am
6am
9am
12pm
3pm
6pm
9pm

Quick answers

CDT is 15 hours behind AEST. CDT uses GMT -5, and AEST uses GMT +10 for this comparison.

For example, 4:30 am CDT is 7:30 pm AEST. Use the converter above to adjust the date or time and create a shareable meeting link.

Best meeting overlap: 5pm-6pm CDT, which is 8am-9am AEST (next day).

Compare CDT time with AEST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.

Time Difference

Central Daylight Time is 15 hours behind Australian Eastern Standard Time
4:30 am04:30 in CDT is 7:30 pm19:30 in AEST

CDT to AEST call time
Best time for a conference call or a meeting is between 5pm-6pm in CDT which corresponds to 8am-9am in AEST (next day)

4:30 am04:30 Central Daylight Time (CDT). Offset UTC -5:00 hours
7:30 pm19:30 Australian Eastern Standard Time (AEST). Offset UTC +10:00 hours

4:30 am04:30 CDT / 7:30 pm19:30 AEST

CDTAEST
12am (midnight)3pm
1am4pm
2am5pm
3am6pm
4am7pm
5am8pm
6am9pm
7am10pm
8am11pm
9am12am (midnight)
10am1am
11am2am
12pm (noon)3am
1pm4am
2pm5am
3pm6am
4pm7am
5pm8am
6pm9am
7pm10am
8pm11am
9pm12pm (noon)
10pm1pm
11pm2pm
00:0015:00
01:0016:00
02:0017:00
03:0018:00
04:0019:00
05:0020:00
06:0021:00
07:0022:00
08:0023:00
09:0000:00
10:0001:00
11:0002:00
12:0003:00
13:0004:00
14:0005:00
15:0006:00
16:0007:00
17:0008:00
18:0009:00
19:0010:00
20:0011:00
21:0012:00
22:0013:00
23:0014:00

Central Daylight Time

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

Countries using this time zone: Canada, Mexico, United States

Principal Cities: The largest city in the CDT time zone is Chicago in the United States, with about 2.696 million people. Other major cities in this time zone include Houston, Ciudad Juarez, San Antonio, Dallas.

French: HAC - Heure Avancée du Centre

Spanish: CT - Zona Centro

CDT Time Zone Geo Map
CDT timezone map

Daylight Saving: Central Daylight Time (CDT) is a daylight saving/summer time zone. During winter, some places set clocks back one hour and observe Central Standard Time (CST).

Daylight saving time clock moves forward for one hour from 2am to 3amStart: Central Daylight Time (CDT) started on Sunday, March 8, 2026 at 2:00 am local time and clocks were set one hour forward to Sunday, March 8, 2026, 3:00 am. Daylight saving starts annually on the second Sunday of March

Daylight saving time clock moves back for one hour from 2am to 1amEnd: Central Daylight Time (CDT) ends on Sunday, November 1, 2026 at 2:00 am local time and clocks are set one hour back to Sunday, November 1, 2026, 1:00 am local standard time instead. Daylight saving ends annually on the first Sunday of November

CDT 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 an offset of five hours to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Romeo - Military abbreviation for CDT
  • R - short form of 'Romeo'
IANA/Olson: Reflects CDT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Chicago
  • America/Indiana/Knox
  • America/Indiana/Tell_City
  • America/Knox_IN
  • America/Matamoros
  • America/Menominee
  • America/North_Dakota/Beulah
  • America/North_Dakota/Center
  • America/North_Dakota/New_Salem
  • America/Ojinaga
  • America/Rainy_River
  • America/Rankin_Inlet
  • America/Resolute
  • America/Winnipeg
  • CST6CDT
  • Canada/Central
  • US/Central
  • US/Indiana-Starke
CDT Abbreviation: Several time zones share CDT abbreviation and it could refer to these time zones
  • Central Daylight Time - UTC -5
  • Cuba Daylight Time - UTC -4
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

Australian Eastern Standard Time

Offset: AEST is 10 hours ahead Greenwich Mean Time (GMT) and is used in Australia

Countries using this time zone: Australia

Principal Cities: The largest city in the AEST time zone is Sydney in Australia, with about 4.627 million people. Other major cities in this time zone include Melbourne, Brisbane, Gold Coast, Canberra.

AEST Time Zone Geo Map
AEST timezone map

Daylight Saving: This is a standard time zone. During summer, some places set clocks forward one hour for daylight saving time and observe Australian Eastern Daylight Time (AEDT).

Daylight saving time clock moves back for one hour from 3am to 2amStart: Australian Eastern Standard Time (AEST) started on Sunday, April 5, 2026 at 3:00 am local time and clocks were set one hour back to Sunday, April 5, 2026, 2:00 am. Standard time starts annually on the first Sunday of April.

Daylight saving time clock moves forward for one hour from 2am to 3amEnd: Australian Eastern Standard Time (AEST) ends on Sunday, October 4, 2026 at 2:00 am local time and clocks are set one hour forward to Sunday, October 4, 2026, 3:00 am local daylight time instead. Standard time ends annually on the first Sunday of October.

Australian Eastern Standard Time (AEST) is used in Queensland, Victoria, Tasmania, New South Wales (except Broken Hill), Australian Capital Territory and in folling major cities Brisbane, Sydney, Melbourne, Hobart, Canberra

Only part of Australia observe daylight saving. It is used in New South Wales, Victoria, South Australia, Tasmania, and the Australian Capital Territory. Daylight saving is not observed in Queensland, Western Australia or the Northern Territory.

AEST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +10 - basic short
  • +1000 - basic
  • +10:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +1000 - sign character (+) followed by a four digit time providing hours (10) and minutes (00) of the offset. Indicates an offset of ten hours to the east of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Kilo - Military abbreviation for AEST
  • K - short form of 'Kilo'
IANA/Olson: Reflects AEST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Antarctica/Macquarie
  • Australia/ACT
  • Australia/Brisbane
  • Australia/Canberra
  • Australia/Currie
  • Australia/Hobart
  • Australia/Lindeman
  • Australia/Melbourne
  • Australia/NSW
  • Australia/Queensland
  • Australia/Sydney
  • Australia/Tasmania
  • Australia/Victoria
Time zones with the GMT +10 offset:
  • AEST - Australian Eastern Standard Time
  • CHUT - Chuuk Time
  • ChST - Chamorro Standard Time
  • K - Kilo Time Zone
  • KDT - Korea Daylight Time
  • PGT - Papua New Guinea Time
  • VLAT - Vladivostok Time
  • YAKST - Yakutsk Summer Time
  • YAPT - Yap Time