Updating current time…
GMT
12am
3am
6am
9am
12pm
3pm
6pm
9pm
The United Kingdom is on summer time: BST (UTC+1) until Sun, Oct 25.

Iceland and Ghana stay on GMT (UTC+0).

Sri LankaSLST
UTC+5:30
12am
3am
6am
9am
12pm
3pm
6pm
9pm

Quick answers

Selected conversion

12:00 pm12:00 GMT (UTC+0), Oct 13, 2026 = 5:30 pm17:30 SLST (UTC+5:30), Oct 13, 2026

GMT is 5 hours and 30 minutes behind Colombo.

How the time difference changes

GMT is 5 hours and 30 minutes behind Colombo year-round.

Working hours of 9:00 am to 5:00 pm in GMT correspond to 2:30 pm to 10:30 pm in Colombo.Working hours of 09:00 to 17:00 in GMT correspond to 14:30 to 22:30 in Colombo.

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

Time Difference

Greenwich Mean Time is 5 hours and 30 minutes behind SLST (Sri Lanka Standard Time).
12:00 pm12:00 in GMT is 5:30 pm17:30 in Colombo, Sri Lanka

GMT to Colombo call time
Best time for a conference call or a meeting is between 9am-11:30am09:00-11:30 in GMT which corresponds to 2:30pm-5pm14:30-17:00 in Colombo

12:00 pm12:00 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
5:30 pm17:30 SLST (Sri Lanka Standard Time) (Colombo, Sri Lanka). Offset UTC +5:30 hours

12:00 pm12:00 GMT / 5:30 pm17:30 Colombo, Sri Lanka

Choose an hour to update the converter. Day labels such as “next day” or “+1” are relative to the selected date in the first column. Use Up and Down arrow keys, Home or End to move between hours, then Enter or Space to select.

Hourly time comparison
GMTColombo, Sri Lanka
5:30am
6:30am
7:30am
8:30am
9:30am
10:30am
11:30am
12:30pm
1:30pm
2:30pm
3:30pm
4:30pm
5:30pm
6:30pm
7:30pm
8:30pm
9:30pm
10:30pm
11:30pm
12:30am next day
1:30am next day
2:30am next day
3:30am next day
4:30am next day
05:30
06:30
07:30
08:30
09:30
10:30
11:30
12:30
13:30
14:30
15:30
16:30
17:30
18:30
19:30
20:30
21:30
22:30
23:30
00:30 next day
01:30 next day
02:30 next day
03:30 next day
04:30 next day

Greenwich Mean Time

Offset: GMT is the same as Greenwich Mean Time (GMT).

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 the United Kingdom, with about 8.962 million people. Other major cities in this time zone include Abidjan, Bamako, Dakar, Kumasi.

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 the two are the same. In the military, GMT is known as Zulu time. Greenwich Mean Time was the same as Universal Time (UT), a standard astronomical concept used in many technical fields, until the introduction of UTC in 1972.

Map of the areas on Greenwich Mean Time (GMT)
GMT all year GMT part of the year

Today the lighter areas are on UTC+1 (British Summer Time, Irish Standard Time).

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 - Coordinated Universal Time
  • WT - Western Sahara Standard Time
  • Z - Zulu Time Zone

Colombo Time Zone and Facts

Time Zone

Abbreviation / Offset
SLST – Sri Lanka Standard Time, UTC+5:30 (no daylight saving time)

Colombo Facts

Country
Sri Lanka
Alternative Names
CMB, Colombo, Columbo, Columbum, Kalomba, Kolombas, Kolombo, Kolompo, Kolonbo, ge lin bao, kalambo, kalombo, ke lun po, kealambea, kholambo, klmbw, kolabo, kolambo, kollombo, kolumpu, kolunbu, koronbo, kwlmbw, kwlwmbw, qwlwmbw, Κολόμπο, Каломба, Коломбо, Կոլոմբո, קולומבו, كولمبو, كولومبو, کلمبو, کولمبو, ކޮޅުނބު, कोलंबो, कोलम्बो, কলম্বো, ਕੋਲੰਬੋ, કોલંબો, କଲୋମ୍ବୋ, கொழும்பு, కొలంబో, ಕೊಲಂಬೊ, കൊളംബോ, කොළඹ, ෙකාළඹ, โคลัมโบ, ཁོ་ལུམ་པོ།, ကိုလံဘိုမြို့, კოლომბო, ኮሎምቦ, コロンボ, 可倫坡, 哥林堡, 콜롬보
Population
648,034
Currency
Rupee (LKR)
Geographic Coordinates
6° 56' N Latitude / 79° 50' E Longitude
International Dialing Code
+94