IST
India Standard Time
GMT +5:30
12am
3am
6am
9am
12pm
3pm
6pm
9pm
BTT
Bhutan Time
GMT +6
12am
3am
6am
9am
12pm
3pm
6pm
9pm

Quick answers

IST is 30 minutes behind BTT. IST uses GMT +5:30, and BTT uses GMT +6 for this comparison.

For example, 5:30 pm IST is 6:00 pm BTT. Use the converter above to adjust the date or time and create a shareable meeting link.

Best meeting overlap: 9am-4:30pm IST, which is 9:30am-5pm BTT.

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

Time Difference

India Standard Time is 0 hours and 30 minutes behind Bhutan Time
5:30 pm17:30 in IST is 6:00 pm18:00 in BTT

IST to BTT call time
Best time for a conference call or a meeting is between 9am-4:30pm in IST which corresponds to 9:30am-5pm in BTT

5:30 pm17:30 India Standard Time (IST). Offset UTC +5:30 hours
6:00 pm18:00 Bhutan Time (BTT). Offset UTC +6:00 hours

5:30 pm17:30 IST / 6:00 pm18:00 BTT

ISTBTT
12am (midnight)12:30 am
1am1:30 am
2am2:30 am
3am3:30 am
4am4:30 am
5am5:30 am
6am6:30 am
7am7:30 am
8am8:30 am
9am9:30 am
10am10:30 am
11am11:30 am
12pm (noon)12:30 pm
1pm1:30 pm
2pm2:30 pm
3pm3:30 pm
4pm4:30 pm
5pm5:30 pm
6pm6:30 pm
7pm7:30 pm
8pm8:30 pm
9pm9:30 pm
10pm10:30 pm
11pm11:30 pm
00:0000:30
01:0001:30
02:0002:30
03:0003:30
04:0004:30
05:0005:30
06:0006:30
07:0007:30
08:0008:30
09:0009:30
10:0010:30
11:0011:30
12:0012:30
13:0013:30
14:0014:30
15:0015:30
16:0016:30
17:0017:30
18:0018:30
19:0019:30
20:0020:30
21:0021:30
22:0022:30
23:0023:30

India Standard Time

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

Countries using this time zone: India

Principal Cities: The largest city in the IST time zone is Mumbai in India, with about 12.692 million people. Other major cities in this time zone include Delhi, Bangalore, Kolkata, Chennai.

Daylight Saving: Clocks in India Standard Time (IST) do not change for daylight saving time, so IST stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter.

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 an offset of five hours and thirty minutes 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

Bhutan Time

Offset: BTT is 6 hours ahead Greenwich Mean Time (GMT) and is used in Asia

Countries using this time zone: Bhutan

Principal Cities: The largest city in the BTT time zone is Thimphu in Bhutan, with about 98,676 people. Other major cities in this time zone include Punakha, Tsirang, Phuntsholing.

Daylight Saving: Clocks in Bhutan Time (BTT) do not change for daylight saving time, so BTT stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter.

BTT Time Zone Geo Map
BTT timezone map

BTT representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +06 - basic short
  • +0600 - basic
  • +06:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0600 - sign character (+) followed by a four digit time providing hours (06) and minutes (00) of the offset. Indicates an offset of six hours to the east of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Foxtrot - Military abbreviation for BTT
  • F - short form of 'Foxtrot'
Time zones with the GMT +6 offset:
  • ALMT - Alma-Ata Time
  • BST - Bangladesh Standard Time
  • BDT - Bangladesh Time
  • BTT - Bhutan Time
  • F - Foxtrot Time Zone
  • IOT - Indian Chagos Time
  • KGT - Kyrgyzstan Time
  • OMST - Omsk Standard Time
  • QYZT - Qyzylorda Time
  • XJT - Xinjiang Time
  • YEKST - Yekaterinburg Summer Time