GMT/IST
Greenwich Mean Time
GMT +0
IST automatically adjusted to GMT time zone, that is in use
CET/CEST
Central European Time
GMT +1
CEST automatically adjusted to CET time zone, that is in use

Time Difference

Greenwich Mean Time is 1 hours behind Central European Time
3:30 pm15:30 in GMT is 4:30 pm16:30 in CET

IST to CEST call time
Best time for a conference call or a meeting is between 8am-5pm in IST which corresponds to 9am-6pm in CEST

3:30 pm15:30 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
4:30 pm16:30 Central European Time (CET). Offset UTC +1:00 hour

3:30 pm15:30 GMT / 4:30 pm16:30 CET

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

Irish Standard Time

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

Countries: It is used in following countries: Ireland

Principal Cities: The largest city in the IST timezone is Dublin from Ireland with population about 1.024 million people. Other major cities in the area are Cork, Dun Laoghaire, Luimneach, Gaillimh

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.

IST Time Zone Geo Map
IST timezone map

IST 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 one hour and zero minutes time differences to the east of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Alpha - Military abbreviation for IST
  • A - short form of 'Alpha'
IANA/Olson: Reflects IST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Eire
  • Europe/Dublin
IST Abbreviation: Several time zones share IST abbreviation and it could refer to these time zones
  • India Standard Time - UTC +5:30
  • Irish Standard Time - UTC +1
  • Israel Standard Time - UTC +2
  • Iran Standard Time - UTC +3:30
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

Central European Summer Time

Offset: CEST is 2 hours ahead Greenwich Mean Time (GMT) and is used in Europe

Countries: It is used in following countries: Andorra, Albania, Austria, Bosnia & Herzegovina, Belgium, Switzerland, Czech Republic, Germany, Denmark, Spain, France, Gibraltar, Croatia, Hungary, Italy, Liechtenstein, Luxembourg, Monaco, Montenegro, North Macedonia, Malta, Netherlands, Norway, Poland, Serbia, Sweden, Slovenia, Svalbard & Jan Mayen, Slovakia, San Marino, Vatican City

Principal Cities: The largest city in the CEST timezone is Berlin from Germany with population about 3.426 million people. Other major cities in the area are Madrid, Rome, Paris, Budapest

German: MESZ - Mitteleuropäische Sommerzeit

CEST Time Zone Geo Map
CEST timezone map

Daylight Saving: Central European Summer Time (CEST) is a daylight saving/summer time zone, however during winter some places adjust time for one hour back and observe Central European Time (CET).

Daylight saving time clock moves back for one hour from 3am to 2amEnd: Central European Summer Time (CEST) has ended on Sunday, October 27, 2024 at 3:00 am local time and clocks were set one hour back to Sunday, October 27, 2024, 2:00 am local standard time instead. Daylight saving ends annually the on last Sunday of October

Daylight saving time clock moves forward for one hour from 2am to 3amStart: Central European Summer Time (CEST) starts on Sunday, March 30, 2025 at 2:00 am local time and clocks are set one hour forward to Sunday, March 30, 2025, 3:00 am. Daylight saving starts annually the on last Sunday of March

CEST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +02 - basic short
  • +0200 - basic
  • +02:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0200 - sign character (+) followed by a four digit time providing hours (02) and minutes (00) of the offset. Indicates two hour and zero minutes time differences to the east of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Bravo - Military abbreviation for CEST
  • B - short form of 'Bravo'
IANA/Olson: Reflects CEST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Africa/Ceuta
  • Arctic/Longyearbyen
  • Atlantic/Jan_Mayen
  • CET
  • Europe/Amsterdam
  • Europe/Andorra
  • Europe/Belgrade
  • Europe/Berlin
  • Europe/Bratislava
  • Europe/Brussels
  • Europe/Budapest
  • Europe/Busingen
  • Europe/Copenhagen
  • Europe/Gibraltar
  • Europe/Ljubljana
  • Europe/Luxembourg
  • Europe/Madrid
  • Europe/Malta
  • Europe/Monaco
  • Europe/Oslo
  • Europe/Paris
  • Europe/Podgorica
  • Europe/Prague
  • Europe/Rome
  • Europe/San_Marino
  • Europe/Sarajevo
  • Europe/Skopje
  • Europe/Stockholm
  • Europe/Tirane
  • Europe/Vaduz
  • Europe/Vatican
  • Europe/Vienna
  • Europe/Warsaw
  • Europe/Zagreb
  • Europe/Zurich
  • Poland
Time zones with the GMT +2 offset:
  • CEST - Central European Summer Time
  • EET - Eastern European Time
  • MESZ - Mitteleuropäische Sommerzeit
  • B - Bravo Time Zone
  • CAT - Central Africa Time
  • IST - Israel Standard Time
  • SAST - South Africa Standard Time
  • WAST - West Africa Summer Time