AST
Atlantic Standard Time
GMT -4
PST/PDT
Pacific Standard Time
GMT -8
PDT automatically adjusted to PST time zone, that is in use

Time Difference

Atlantic Standard Time is 4 hours ahead of Pacific Standard Time
So 2:30 am02:30 in AST is 10:30 pm22:30 in PST

2:30 am02:30 Atlantic Standard Time (AST). Offset UTC -4:00 hours
10:30 pm22:30 Pacific Standard Time (PST). Offset UTC -8:00 hours

2:30 am02:30 AST / 10:30 pm22:30 PST

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

Atlantic Standard Time

Offset: AST is 4 hours behind Greenwich Mean Time (GMT) and is used in North America

Countries: It is used in following countries: Antigua & Barbuda, Anguilla, Aruba, Barbados, St Barthelemy, Bermuda, Caribbean NL, Canada, Curaçao, Dominica, Dominican Republic, Grenada, Greenland, Guadeloupe, St Kitts & Nevis, St Lucia, St Martin (French), Martinique, Montserrat, Puerto Rico, St Maarten (Dutch), Trinidad & Tobago, St Vincent, Virgin Islands (UK), Virgin Islands (US)

Principal Cities: The largest city in the AST timezone is Santo Domingo from Dominican Republic with population about 2.202 million people. Other major cities in the area are Santiago de los Caballeros, Santo Domingo Oeste, San Juan, Halifax

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 Atlantic Daylight Time (ADT).

Start: AST starts annually on the same date and time. and clocks were set one hour back on Sunday, November 3, 2019, at 2:00 (2:00 am) local time.

End: AST ends annually on the same date and time. and clocks are set one hour forward on Sunday, March 8, 2020, at 2:00 (2:00 am) local time.

French: HNA - Heure Normale de l'Atlantique

Spanish: AST - Tiempo Estándar del Atlántico

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

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -04 - basic short
  • -0400 - basic
  • -04:00 - extended

Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0400 - sign character (-) followed by a four digit time providing hours (04) and minutes (00) of the offset. Indicates four 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
  • Quebec - Military abbreviation for AST
  • Q - short form of 'Quebec'

IANA/Olson: Reflects AST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Anguilla
  • America/Antigua
  • America/Aruba
  • America/Barbados
  • America/Blanc-Sablon
  • America/Curacao
  • America/Dominica
  • America/Glace_Bay
  • America/Goose_Bay
  • America/Grenada
  • America/Guadeloupe
  • America/Halifax
  • America/Kralendijk
  • America/Lower_Princes
  • America/Marigot
  • America/Martinique
  • America/Moncton
  • America/Montserrat
  • America/Port_of_Spain
  • America/Puerto_Rico
  • America/Santo_Domingo
  • America/St_Barthelemy
  • America/St_Kitts
  • America/St_Lucia
  • America/St_Thomas
  • America/St_Vincent
  • America/Thule
  • America/Tortola
  • America/Virgin
  • Atlantic/Bermuda
  • Canada/Atlantic

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

  • Atlantic Standard Time - UTC -4
  • Arabia Standard Time - UTC +3

Time zones with the GMT -4 offset:

  • AST - Atlantic Standard Time
  • EDT - Eastern Daylight Time
  • AMT - Amazon Time
  • BOT - Bolivia Time
  • CDT - Cuba Daylight Time
  • CLT - Chile Standard Time
  • FKT - Falkland Island Time
  • GYT - Guyana Time
  • PYT - Paraguay Time
  • Q - Quebec Time Zone
  • VET - Venezuelan Standard Time
  • -04 -


Pacific Daylight Time

Offset: PDT is 7 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 PDT 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

Daylight Saving: Pacific Daylight Time (PDT) is a daylight saving/summer timezone, however during winter some places adjust time for one hour back and observe Pacific Standard Time (PST).

End: PDT ends annually on the same date and time. and clocks were set one hour back on Sunday, November 3, 2019, at 2:00 (2:00 am) local time.

Start: PDT starts annually on the same date and time. and clocks are set one hour forward on Sunday, March 8, 2020, at 2:00 (2:00 am) local time.

French: HAP - Heure Avancée du Pacifique

Spanish: PT - Zona Noroeste

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

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -07 - basic short
  • -0700 - basic
  • -07:00 - extended

Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0700 - sign character (-) followed by a four digit time providing hours (07) and minutes (00) of the offset. Indicates seven 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
  • Tango - Military abbreviation for PDT
  • T - short form of 'Tango'

IANA/Olson: Reflects PDT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Dawson
  • America/Ensenada
  • America/Los_Angeles
  • America/Santa_Isabel
  • America/Tijuana
  • America/Vancouver
  • America/Whitehorse
  • Canada/Pacific
  • Canada/Yukon
  • Mexico/BajaNorte
  • PST8PDT
  • US/Pacific
  • US/Pacific-New

Time zones with the GMT -7 offset:

  • MST - Mountain Standard Time
  • PDT - Pacific Daylight Time
  • T - Tango Time Zone