GMT
Greenwich Mean Time
GMT +0
12am
3am
6am
9am
12pm
3pm
6pm
9pm
WEST
Western European Summer Time
GMT +1
12am
3am
6am
9am
12pm
3pm
6pm
9pm
WEST is not used on this date
This converter keeps WEST at GMT +1. Lisbon uses WET (GMT +0) on this date. Open the WET converter, or choose Lisbon, Las Palmas de Gran Canaria, or Porto for city-specific time.

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

Time Difference

Greenwich Mean Time is 1 hour behind Western European Summer Time
12:00 pm12:00 in GMT is 1:00 pm13:00 in WEST

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

12:00 pm12:00 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
1:00 pm13:00 Western European Summer Time (WEST). Offset UTC +1:00 hour

12:00 pm12:00 GMT / 1:00 pm13:00 WEST

GMTWEST
12am (midnight)1am
1am2am
2am3am
3am4am
4am5am
5am6am
6am7am
7am8am
8am9am
9am10am
10am11am
11am12pm (noon)
12pm (noon)1pm
1pm2pm
2pm3pm
3pm4pm
4pm5pm
5pm6pm
6pm7pm
7pm8pm
8pm9pm
9pm10pm
10pm11pm
11pm12am (midnight)
00:0001:00
01:0002:00
02:0003:00
03:0004:00
04:0005:00
05:0006:00
06:0007:00
07:0008:00
08:0009:00
09:0010:00
10:0011:00
11:0012:00
12:0013:00
13:0014:00
14:0015:00
15:0016:00
16:0017:00
17:0018:00
18:0019:00
19:0020:00
20:0021:00
21:0022:00
22:0023:00
23:0000:00

Greenwich Mean Time

Offset: GMT is 0 hours ahead Greenwich Mean Time (GMT) and is used in Europe

Countries using this time zone: 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 time zone is London in United Kingdom, with about 7.557 million people. Other major cities in this time zone include 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 the zero UTC/GMT offset.
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
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

Western European Summer Time

Offset: WEST is 1 hour ahead Greenwich Mean Time (GMT) and is used in Europe

Countries using this time zone: Spain, Faroe Islands, Portugal

Principal Cities: The largest city in the WEST time zone is Lisbon in Portugal, with about 517,802 people. Other major cities in this time zone include Las Palmas de Gran Canaria, Porto, Santa Cruz de Tenerife, Amadora.

German: WESZ - Westeuropäische Sommerzeit

WEST Time Zone Geo Map
WEST timezone map

Daylight Saving: Western European Summer Time (WEST) is a daylight saving/summer time zone, but some places set clocks back one hour during winter and observe Western European Time (WET).

Daylight saving time clock moves forward for one hour from 2am to 3amEnd: Western European Summer Time (WEST) ended on Sunday, October 26, 2025 at 2:00 am local time and clocks were set one hour back to Sunday, October 26, 2025, 1:00 am local standard time instead. Daylight saving ends annually on the last Sunday of October

Daylight saving time clock moves back for one hour from 1am to 12amStart: Western European Summer Time (WEST) starts on Sunday, March 29, 2026 at 1:00 am local time and clocks are set one hour forward to Sunday, March 29, 2026, 2:00 am. Daylight saving starts annually on the last Sunday of March

WEST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +01 - basic short
  • +0100 - basic
  • +01:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0100 - sign character (+) followed by a four digit time providing hours (01) and minutes (00) of the offset. Indicates an offset of one hour to the east of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Alpha - Military abbreviation for WEST
  • A - short form of 'Alpha'
IANA/Olson: Reflects WEST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Atlantic/Canary
  • Atlantic/Faeroe
  • Atlantic/Faroe
  • Atlantic/Madeira
  • Europe/Lisbon
  • Portugal
  • WET
Time zones with the GMT +1 offset:
  • BST - British Summer Time
  • CET - Central European Time
  • IST - Irish Standard Time
  • WEST - Western European Summer Time
  • A - Alpha Time Zone
  • CET - Central European Time
  • MEZ - Mitteleuropäische Zeit
  • WAT - West Africa Time
  • WST - Western Sahara Summer Time
  • BMT - Biel Mean Time