PDT/PST
Pacific Daylight Time
GMT -7
PST automatically adjusted to PDT time zone, that is in use
IST
India Standard Time
GMT +5:30
CDT/CST
Central Daylight Time
GMT -5
CST automatically adjusted to CDT time zone, that is in use
GMT
Greenwich Mean Time
GMT +0
AEDT
Australian Eastern Daylight Time
GMT +11
AEDT is NOT in use by many locations
AEST (Australian Eastern Standard Time) is used instead. Switch to AEST time zone or select one of the cities Sydney, Melbourne, Canberra) for automatic timezone change.

Time Difference

Pacific Daylight Time is 12 hours and 30 minutes behind India Standard Time and 2 hours behind Central Daylight Time and 7 hours behind Greenwich Mean Time and 18 hours behind Australian Eastern Daylight Time
4:30 am04:30 in PDT is 5:00 pm17:00 in IST and is 6:30 am06:30 in CDT and is 11:30 am11:30 in GMT and is 10:30 pm22:30 in AEDT

PST to IST call time
Best time for a conference call or a meeting is between 6am-8am in PST which corresponds to 7:30pm-9:30pm in IST
PST to CST call time
Best time for a conference call or a meeting is between 8am-4pm in PST which corresponds to 10am-6pm in CST
PST to GMT call time
Best time for a conference call or a meeting is between 8am-10am in PST which corresponds to 4pm-6pm in GMT
PST to AEDT call time
Best time for a conference call or a meeting is between 3:30am-5:30am in PST which corresponds to 10:30pm-12:30pm in AEDT

4:30 am04:30 Pacific Daylight Time (PDT). Offset UTC -7:00 hours
5:00 pm17:00 India Standard Time (IST). Offset UTC +5:30 hours
6:30 am06:30 Central Daylight Time (CDT). Offset UTC -5:00 hours
11:30 am11:30 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
10:30 pm22:30 Australian Eastern Daylight Time (AEDT). Offset UTC +11:00 hours

4:30 am04:30 PDT / 5:00 pm17:00 IST / 6:30 am06:30 CDT / 11:30 am11:30 GMT / 10:30 pm22:30 AEDT

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

Pacific Standard Time

Offset: PST is 8 hours behind Greenwich Mean Time (GMT) and is used in North America

Countries: It is used in following countries: Canada, Mexico, United States

Principal Cities: The largest city in the PST timezone is Los Angeles from USA with population about 3.793 million people. Other major cities in the area are Vancouver, Tijuana, San Diego, San Jose

French: HNP - Heure Normale du Pacifique

Spanish: PT - Tiempo del Pacífico, PT - Zona Noroeste

PST Time Zone Geo Map
PST 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 Pacific Daylight Time (PDT).

Daylight saving time clock moves forward for one hour from 2am to 3amEnd: Pacific Standard Time (PST) has ended on Sunday, March 9, 2025 at 2:00 am local time and clocks were set one hour forward to Sunday, March 9, 2025, 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: Pacific Standard Time (PST) starts on Sunday, November 2, 2025 at 2:00 am local time and clocks are set one hour back to Sunday, November 2, 2025, 1:00 am. Standard time starts annually the on first Sunday of November.

PST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -08 - basic short
  • -0800 - basic
  • -08:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0800 - sign character (-) followed by a four digit time providing hours (08) and minutes (00) of the offset. Indicates eight 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
  • Uniform - Military abbreviation for PST
  • U - short form of 'Uniform'
IANA/Olson: Reflects PST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Ensenada
  • America/Los_Angeles
  • America/Santa_Isabel
  • America/Tijuana
  • America/Vancouver
  • Canada/Pacific
  • Mexico/BajaNorte
  • PST8PDT
  • US/Pacific
PST Abbreviation: Several time zones share PST abbreviation and it could refer to these time zones
  • Pacific Standard Time - UTC -8
  • Pitcairn Standard Time - UTC -8
  • Peru Standard Time - UTC -5
Time zones with the GMT -8 offset:
  • AKDT - Alaska Daylight Time
  • PST - Pacific Standard Time
  • PT - Pacific Time
  • PST - Pitcairn Standard Time
  • U - Uniform Time Zone

India Standard Time

Offset: IST is 5 hours and 30 minutes ahead Greenwich Mean Time (GMT) and is used in Asia

Countries: It is used in following countries: India

Principal Cities: The largest city in the IST timezone is Mumbai from India with population about 12.692 million people. Other major cities in the area are Delhi, Bangalore, Kolkata, Chennai

Daylight Saving: India Standard Time (IST) is not adjusted for daylight saving therefore IST remains the same through out the year. This means, unlike some time zones where the clock is set forward by one hour every summer and backward by one hour during winter to adjust for daylight saving, India Standard Time remains the same

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
  • +0530 - basic
  • +05:30 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0530 - sign character (+) followed by a four digit time providing hours (05) and minutes (30) of the offset. Indicates five hour and thirty minutes time differences to the east of the zero meridian.
IANA/Olson: Reflects IST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Asia/Calcutta
  • Asia/Kolkata
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

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 9, 2025 at 2:00 am local time and clocks were set one hour forward to Sunday, March 9, 2025, 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 2, 2025 at 2:00 am local time and clocks are set one hour back to Sunday, November 2, 2025, 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

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+03:00 - UTC +3
  • GMT - UTC +1
  • GMT+11:00 - UTC +11
  • 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

Australian Eastern Daylight Time

Offset: AEDT is 11 hours ahead Greenwich Mean Time (GMT) and is used in Australia

Countries: It is used in following countries: Australia

Principal Cities: The largest city in the AEDT timezone is Sydney from Australia with population about 4.627 million people. Other major cities in the area are Melbourne, Canberra, Newcastle, Wollongong

AEDT Time Zone Geo Map
AEDT timezone map

Daylight Saving: Australian Eastern Daylight Time (AEDT) is a daylight saving/summer time zone, however during winter some places adjust time for one hour back and observe Australian Eastern Standard Time (AEST).

Daylight saving time clock moves back for one hour from 3am to 2amEnd: Australian Eastern Daylight Time (AEDT) has ended on Sunday, April 6, 2025 at 3:00 am local time and clocks were set one hour back to Sunday, April 6, 2025, 2:00 am local standard time instead. Daylight saving ends annually the on first Sunday of April

Daylight saving time clock moves forward for one hour from 2am to 3amStart: Australian Eastern Daylight Time (AEDT) starts on Sunday, October 5, 2025 at 2:00 am local time and clocks are set one hour forward to Sunday, October 5, 2025, 3:00 am. Daylight saving starts annually the on first Sunday of October

Australian Eastern Daylight Time (AEDT) is observer in New South Wales (except Broken Hill and Lord Howe Island), Victoria, Tasmania, Australian Capital Territory, Sydney, Melbourne, Hobart, Canberra AEDT is equal to Coordinated Universal Time plus 11 hours (UTC +11). During a summer time period, these locations move from AEST to Australian Eastern Daylight Time (AEDT), and clocks are advanced to UTC +11.

Daylight saving or summer time is commonly expressed as AEDT (Australian Eastern Daylight Time). In periods of daylight saving an hour is added to the Local Standard Time.

The regulation of time is a State Government responsibility. Changes to the period of daylight saving may be made by regulation. Legislation to harmonise daylight saving in NSW with the south-eastern states and the ACT was passed by the NSW Parliament on 23 October 2007.

History of daylight saving in New South Wales
Daylight saving operated nationally for single summer during World War I from 1 January 1917 to 25 March 1917 and during World War II for three summers in a row, starting on 1 January 1942. Daylight saving was re-introduced for third time in New South Wales on 31 October 1971 after New South Wales Parliament passed the Standard Time Act 1971. A referendum held on 1 May 1976 proposed that daylight saving should be on a permanent basis. The ballot paper stated: "At present there is a period commonly called 'daylight saving' by which time is advanced by one hour for the period commencing on the last Sunday in October in each year and ending on the first Sunday in March in the following year. Electors were then asked to answer YES or NO to the question: Are you in favour of daylight saving? 1,882,770 electors were in favour, 868,900 were against and 35,507 votes were informal.\" The period of daylight saving is prescribed by the Daylight Saving Regulations 2008, made under the Daylight Saving Act 2007. Since April 2008, daylight saving has been synchronised across Tasmania, New South Wales, Victoria, the ACT and South Australia, although South Australia remains half an hour behind throughout the year due to the observance of Australian Central Standard Time.

Which is correct Daylight Savings or Daylight Saving (with or without the 's' at the end)? The correct spelling in Australia is without the 's'.

AEDT representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +11 - basic short
  • +1100 - basic
  • +11:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +1100 - sign character (+) followed by a four digit time providing hours (11) and minutes (00) of the offset. Indicates eleven 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
  • Lima - Military abbreviation for AEDT
  • L - short form of 'Lima'
IANA/Olson: Reflects AEDT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Antarctica/Macquarie
  • Australia/ACT
  • Australia/Canberra
  • Australia/Currie
  • Australia/Hobart
  • Australia/Melbourne
  • Australia/NSW
  • Australia/Sydney
  • Australia/Tasmania
  • Australia/Victoria
Time zones with the GMT +11 offset:
  • AEDT - Australian Eastern Daylight Time
  • BST - Bougainville Standard Time
  • KOST - Kosrae Time
  • L - Lima Time Zone
  • LHDT - Lord Howe Daylight Time
  • NCT - New Caledonia Time
  • PETT - Kamchatka Time
  • PONT - Pohnpei Standard Time
  • SBT - Solomon IslandsTime
  • VLAST - Vladivostok Summer Time
  • VUT - Vanuatu Time