IST
India Standard Time
GMT +5:30
+01
GMT +1

Time Difference

India Standard Time is 4 hours and 30 minutes ahead of
9:00 pm21:00 in IST is 4:30 pm16:30 in +01

IST to +01 call time
Best time for a conference call or a meeting is between 12:30pm-6pm in IST which corresponds to 8am-1:30pm in +01

9:00 pm21:00 India Standard Time (IST). Offset UTC +5:30 hours
4:30 pm16:30 (+01). Offset UTC +1:00 hour

9:00 pm21:00 IST / 4:30 pm16:30 +01

IST +01
12am (midnight) 7:30 pm
1am 8:30 pm
2am 9:30 pm
3am 10:30 pm
4am 11:30 pm
5am 12:30 am
6am 1:30 am
7am 2:30 am
8am 3:30 am
9am 4:30 am
10am 5:30 am
11am 6:30 am
12pm (noon) 7:30 am
1pm 8:30 am
2pm 9:30 am
3pm 10:30 am
4pm 11:30 am
5pm 12:30 pm
6pm 1:30 pm
7pm 2:30 pm
8pm 3:30 pm
9pm 4:30 pm
10pm 5:30 pm
11pm 6:30 pm
0:00 19:30
1:00 20:30
2:00 21:30
3:00 22:30
4:00 23:30
5:00 0:30
6:00 1:30
7:00 2:30
8:00 3:30
9:00 4:30
10:00 5:30
11:00 6:30
12:00 7:30
13:00 8:30
14:00 9:30
15:00 10:30
16:00 11:30
17:00 12:30
18:00 13:30
19:00 14:30
20:00 15:30
21:00 16:30
22:00 17:30
23:00 18:30

India Standard Time

Offset: IST is 5 hours and 30 minutes ahead Greenwich Mean Time (GMT) and is used in Asia

Countries: It is used in following countries: India

Principal Cities: The largest city in the IST timezone is Mumbai from India with population about 12.692 million people. Other major cities in the area are Delhi, Bangalore, Kolkata, Chennai

Daylight Saving: India Standard Time (IST) is not adjusted for daylight saving therefore IST remains the same through out the year. This means, unlike some time zones where the clock is set forward by one hour every summer and backward by one hour during winter to adjust for daylight saving, India Standard Time remains the same

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
  • +0530 - basic
  • +05:30 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0530 - sign character (+) followed by a four digit time providing hours (05) and minutes (30) of the offset. Indicates five hour and thirty minutes time differences to the east of the zero meridian.
IANA/Olson: Reflects IST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Asia/Calcutta
  • Asia/Kolkata
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

+01

Offset: +01 is 1 hour ahead Greenwich Mean Time (GMT) and is used in Africa

Countries: It is used in following countries: Western Sahara, Morocco

Principal Cities: The largest city in the +01 timezone is Casablanca from Morocco with population about 3.145 million people. Other major cities in the area are Rabat, Fes, Sale, Marrakesh

Daylight Saving: (+01) is not adjusted for daylight saving therefore +01 remains the same through out the year. This means, unlike some time zones where the clock is set forward by one hour every summer and backward by one hour during winter to adjust for daylight saving, remains the same

+01 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 +01
  • A - short form of 'Alpha'
IANA/Olson: Reflects +01 time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Africa/Casablanca
  • Africa/El_Aaiun
  • Etc/GMT-1
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