GMT
Greenwich Mean Time
GMT +0
Y
Yankee Time Zone
GMT -12

Time Difference

Greenwich Mean Time is 12 hours ahead of Yankee Time Zone
5:30 pm17:30 in GMT is 5:30 am05:30 in Y

GMT to Y call time
Best time for a conference call or a meeting is between 7pm-9pm in GMT which corresponds to 7am-9am in Y

5:30 pm17:30 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
5:30 am05:30 Yankee Time Zone (Y). Offset UTC -12:00 hours

5:30 pm17:30 GMT / 5:30 am05:30 Y

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

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+06:00 - UTC +6
  • GMT-01:00 - UTC -1
  • GMT+11:00 - UTC +11
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

Yankee Time Zone

Offset: Y is 12 hours behind Greenwich Mean Time (GMT) and is used in Military

Y representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -12 - basic short
  • -1200 - basic
  • -12:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -1200 - sign character (-) followed by a four digit time providing hours (12) and minutes (00) of the offset. Indicates twelve 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
  • Yankee - Military abbreviation for Y
  • Y - short form of 'Yankee'