IST
India Standard Time
GMT +5:30
12am
3am
6am
9am
12pm
3pm
6pm
9pm
ACDT
Australian Central Daylight Time
GMT +10:30
12am
3am
6am
9am
12pm
3pm
6pm
9pm

Quick answers

IST is 5 hours behind ACDT. IST uses GMT +5:30, and ACDT uses GMT +10:30 for this comparison.

For example, 5:30 pm IST is 10:30 pm ACDT. Use the converter above to adjust the date or time and create a shareable meeting link.

Best meeting overlap: 9am-12pm IST, which is 2pm-5pm ACDT.

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

Time Difference

India Standard Time is 5 hours behind Australian Central Daylight Time
5:30 pm17:30 in IST is 10:30 pm22:30 in ACDT

IST to ACDT call time
Best time for a conference call or a meeting is between 9am-12pm in IST which corresponds to 2pm-5pm in ACDT

5:30 pm17:30 India Standard Time (IST). Offset UTC +5:30 hours
10:30 pm22:30 Australian Central Daylight Time (ACDT). Offset UTC +10:30 hours

5:30 pm17:30 IST / 10:30 pm22:30 ACDT

ISTACDT
12am (midnight)5am
1am6am
2am7am
3am8am
4am9am
5am10am
6am11am
7am12pm (noon)
8am1pm
9am2pm
10am3pm
11am4pm
12pm (noon)5pm
1pm6pm
2pm7pm
3pm8pm
4pm9pm
5pm10pm
6pm11pm
7pm12am (midnight)
8pm1am
9pm2am
10pm3am
11pm4am
00:0005:00
01:0006:00
02:0007:00
03:0008:00
04:0009:00
05:0010:00
06:0011:00
07:0012:00
08:0013:00
09:0014:00
10:0015:00
11:0016:00
12:0017:00
13:0018:00
14:0019:00
15:0020:00
16:0021:00
17:0022:00
18:0023:00
19:0000:00
20:0001:00
21:0002:00
22:0003:00
23:0004:00

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

Australian Central Daylight Time

Offset: ACDT is 10 hours and 30 minutes ahead Greenwich Mean Time (GMT) and is used in Australia

Countries using this time zone: Australia

Principal Cities: The largest city in the ACDT time zone is Adelaide in Australia, with about 1.225 million people. Other major cities in this time zone include Adelaide Hills, Mount Gambier, Morphett Vale, Prospect.

ACDT Time Zone Geo Map
ACDT timezone map

Daylight Saving: Australian Central Daylight Time (ACDT) is a daylight saving/summer time zone. During winter, some places set clocks back one hour and observe Australian Central Standard Time (ACST).

Daylight saving time clock moves forward for one hour from 2am to 3amStart: Australian Central Daylight Time (ACDT) started on Sunday, October 5, 2025 at 2:00 am local time and clocks were set one hour forward to Sunday, October 5, 2025, 3:00 am. Daylight saving starts annually on the first Sunday of October

Daylight saving time clock moves back for one hour from 3am to 2amEnd: Australian Central Daylight Time (ACDT) ends on Sunday, April 5, 2026 at 3:00 am local time and clocks are set one hour back to Sunday, April 5, 2026, 2:00 am local standard time instead. Daylight saving ends annually on the first Sunday of April

ACDT representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +1030 - basic
  • +10:30 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +1030 - sign character (+) followed by a four digit time providing hours (10) and minutes (30) of the offset. Indicates an offset of ten hours and thirty minutes to the east of the zero meridian.
IANA/Olson: Reflects ACDT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Australia/Adelaide
  • Australia/Broken_Hill
  • Australia/South
  • Australia/Yancowinna
Time zones with the GMT +10:30 offset:
  • ACDT - Australian Central Daylight Time
  • LHST - Lord Howe Standard Time