AST/ADT
Atlantic Standard Time
GMT -4
12am
3am
6am
9am
12pm
3pm
6pm
9pm
ADT is not used on this date
This converter uses AST (GMT -4), the offset Moncton uses on this date. Open the AST converter.
EST/EDT
Eastern Standard Time
GMT -5
12am
3am
6am
9am
12pm
3pm
6pm
9pm
EDT is not used on this date
This converter uses EST (GMT -5), the offset New York uses on this date. Open the EST converter.

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

Time Difference

Atlantic Standard Time is 1 hour ahead of Eastern Standard Time
8:00 am08:00 in AST is 7:00 am07:00 in EST

AST to EST call time
Best time for a conference call or a meeting is between 10am-5pm in AST which corresponds to 9am-4pm in EST

8:00 am08:00 Atlantic Standard Time (AST). Offset UTC -4:00 hours
7:00 am07:00 Eastern Standard Time (EST). Offset UTC -5:00 hours

8:00 am08:00 AST / 7:00 am07:00 EST

ASTEST
12am (midnight)11pm
1am12am (midnight)
2am1am
3am2am
4am3am
5am4am
6am5am
7am6am
8am7am
9am8am
10am9am
11am10am
12pm (noon)11am
1pm12pm (noon)
2pm1pm
3pm2pm
4pm3pm
5pm4pm
6pm5pm
7pm6pm
8pm7pm
9pm8pm
10pm9pm
11pm10pm
00:0023:00
01:0000:00
02:0001:00
03:0002:00
04:0003:00
05:0004:00
06:0005:00
07:0006:00
08:0007:00
09:0008:00
10:0009:00
11:0010:00
12:0011:00
13:0012:00
14:0013:00
15:0014:00
16:0015:00
17:0016:00
18:0017:00
19:0018:00
20:0019:00
21:0020:00
22:0021:00
23:0022:00

Atlantic Daylight Time

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

Countries using this time zone: Bermuda, Canada, Greenland

Principal Cities: The largest city in the ADT time zone is Halifax in Canada, with about 359,111 people. Other major cities in this time zone include 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, but some places set clocks back one hour during winter and observe Atlantic Standard Time (AST).

Daylight saving time clock moves forward for one hour from 2am to 3amEnd: Atlantic Daylight Time (ADT) ended on Sunday, November 2, 2025 at 2:00 am local time and clocks were set one hour back to Sunday, November 2, 2025, 1:00 am local standard time instead. Daylight saving ends annually on the first Sunday of November

Daylight saving time clock moves back for one hour from 2am to 1amStart: Atlantic Daylight Time (ADT) starts on Sunday, March 8, 2026 at 2:00 am local time and clocks are set one hour forward to Sunday, March 8, 2026, 3:00 am. Daylight saving starts annually on the 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 an offset of three hours 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
  • 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

Eastern Daylight Time

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

Countries using this time zone: Bahamas, Canada, Haiti, Turks & Caicos Is, United States

Principal Cities: The largest city in the EDT time zone is New York City in the United States, with about 8.175 million people. Other major cities in this time zone include Toronto, Montreal, Brooklyn, Borough of Queens.

French: HAE - Heure Avancée de l'Est

Spanish: EDT - Tiempo de verano del Este, ET - Zona Sureste

EDT Time Zone Geo Map
EDT timezone map

Daylight Saving: Eastern Daylight Time (EDT) is a daylight saving/summer time zone, but some places set clocks back one hour during winter and observe Eastern Standard Time (EST).

Daylight saving time clock moves forward for one hour from 2am to 3amEnd: Eastern Daylight Time (EDT) ended on Sunday, November 2, 2025 at 2:00 am local time and clocks were set one hour back to Sunday, November 2, 2025, 1:00 am local standard time instead. Daylight saving ends annually on the first Sunday of November

Daylight saving time clock moves back for one hour from 2am to 1amStart: Eastern Daylight Time (EDT) starts on Sunday, March 8, 2026 at 2:00 am local time and clocks are set one hour forward to Sunday, March 8, 2026, 3:00 am. Daylight saving starts annually on the second Sunday of March

EDT 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 an offset of four hours to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Quebec - Military abbreviation for EDT
  • Q - short form of 'Quebec'
IANA/Olson: Reflects EDT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Detroit
  • America/Fort_Wayne
  • America/Grand_Turk
  • America/Indiana/Indianapolis
  • America/Indiana/Marengo
  • America/Indiana/Petersburg
  • America/Indiana/Vevay
  • America/Indiana/Vincennes
  • America/Indiana/Winamac
  • America/Indianapolis
  • America/Iqaluit
  • America/Kentucky/Louisville
  • America/Kentucky/Monticello
  • America/Louisville
  • America/Montreal
  • America/Nassau
  • America/New_York
  • America/Nipigon
  • America/Pangnirtung
  • America/Port-au-Prince
  • America/Thunder_Bay
  • America/Toronto
  • Canada/Eastern
  • EST5EDT
  • US/East-Indiana
  • US/Eastern
  • US/Michigan
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
  • HLV - Hora Legal de Venezuela
  • PYT - Paraguay Time
  • Q - Quebec Time Zone
  • VET - Venezuelan Standard Time