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

Time Difference

Pacific Standard Time is 4 hours behind Atlantic Standard Time
5:00 am05:00 in PST is 9:00 am09:00 in AST

PDT to ADT call time
Best time for a conference call or a meeting is between 8am-2pm in PDT which corresponds to 12pm-6pm in ADT

5:00 am05:00 Pacific Standard Time (PST). Offset UTC -8:00 hours
9:00 am09:00 Atlantic Standard Time (AST). Offset UTC -4:00 hours

5:00 am05:00 PST / 9:00 am09:00 AST

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

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

French: HAP - Heure Avancée du Pacifique

Spanish: PT - Zona Noroeste

PDT Time Zone Geo Map
PDT timezone map

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

Daylight saving time clock moves back for one hour from 2am to 1amEnd: Pacific Daylight Time (PDT) has ended on Sunday, November 7, 2021 at 2:00 am local time and clocks were set one hour back to Sunday, November 7, 2021, 1:00 am local standard time instead. Daylight saving ends annually the on first Sunday of November

Daylight saving time clock moves forward for one hour from 2am to 3amStart: Pacific Daylight Time (PDT) starts on Sunday, March 13, 2022 at 2:00 am local time and clocks are set one hour forward to Sunday, March 13, 2022, 3:00 am. Daylight saving starts annually the on second Sunday of March

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/Ensenada
  • America/Los_Angeles
  • America/Santa_Isabel
  • America/Tijuana
  • America/Vancouver
  • Canada/Pacific
  • Mexico/BajaNorte
  • PST8PDT
  • US/Pacific
Time zones with the GMT -7 offset:
  • MST - Mountain Standard Time
  • PDT - Pacific Daylight Time
  • YST - Yukon Standard Time
  • T - Tango Time Zone

Atlantic Daylight Time

Offset: ADT is 3 hours behind Greenwich Mean Time (GMT) and is used in North America

Countries: It is used in following countries: Bermuda, Canada, Greenland

Principal Cities: The largest city in the ADT timezone is Halifax from Canada with population about 359,111 people. Other major cities in the area are Sydney, Dartmouth, Saint John, Moncton

French: HAA - Heure Avancée de l'Atlantique

ADT Time Zone Geo Map
ADT timezone map

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

Daylight saving time clock moves back for one hour from 2am to 1amEnd: Atlantic Daylight Time (ADT) has ended on Sunday, November 7, 2021 at 2:00 am local time and clocks were set one hour back to Sunday, November 7, 2021, 1:00 am local standard time instead. Daylight saving ends annually the on first Sunday of November

Daylight saving time clock moves forward for one hour from 2am to 3amStart: Atlantic Daylight Time (ADT) starts on Sunday, March 13, 2022 at 2:00 am local time and clocks are set one hour forward to Sunday, March 13, 2022, 3:00 am. Daylight saving starts annually the on second Sunday of March

ADT representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -03 - basic short
  • -0300 - basic
  • -03:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0300 - sign character (-) followed by a four digit time providing hours (03) and minutes (00) of the offset. Indicates three 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
  • Papa - Military abbreviation for ADT
  • P - short form of 'Papa'
IANA/Olson: Reflects ADT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Glace_Bay
  • America/Goose_Bay
  • America/Halifax
  • America/Moncton
  • America/Thule
  • Atlantic/Bermuda
  • Canada/Atlantic
Time zones with the GMT -3 offset:
  • ADT - Atlantic Daylight Time
  • PMT - Pierre & Miquelon Standard Time
  • PMST - Pierre & Miquelon Standard Time
  • WGT - West Greenland Time
  • AMST - Amazon Summer Time
  • ART - Argentina Time
  • BRT - Brasília time
  • CLST - Chile Summer Time
  • FKST - Falkland Islands Summer Time
  • GFT - French Guiana Time
  • P - Papa Time Zone
  • PYST - Paraguay Summer Time
  • SRT - Suriname Time
  • UYT - Uruguay Time