IST to ACST Time Converter

Convert India Standard Time (IST) to Australian Central Standard Time (ACST). Both time zones are shown live below; current offset between them is 4 hours ahead.

Mumbai · India Standard Time
06:19:16
Thursday, May 14, 2026
GMT+5:30 · UTC+05:30
Adelaide · Australian Central Standard Time
10:19:16
Thursday, May 14, 2026
GMT+9:30 · UTC+09:30

Convert a specific time

From: IST (Mumbai)
To: ACST (Adelaide)
--:--

Daylight Saving status right now

IST (India Standard Time)
Observes DST
No
ACST (Australian Central Standard Time)
Observes DST
Yes
In DST right now
No
Next spring forward
2026-10-04
Offset shift
UTC+09:30 → UTC+10:30

Heads up: ACST observes DST while IST does not. The 4-hour difference shown above will shift by one hour when ACST starts or ends DST.

When can IST and ACST meet?

00
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
IST
ACST
Both zones in working hours (9am-5pm)
One zone working
Off-hours
Columns are hours of the day in Mumbai (IST). Each row shows the local working-hours state in that zone for the same moment in time.
4 hours of overlap during standard 9am-5pm working hours.
Best meeting window: 09:00–12:00 IST (13:00–16:00 ACST).

Hour-by-hour IST to ACST conversion table

IST time (Mumbai)ACST time (Adelaide)Status
00:00 Thu04:00 ThuOff-hours both sides
01:00 Thu05:00 ThuOff-hours both sides
02:00 Thu06:00 ThuOff-hours both sides
03:00 Thu07:00 ThuOff-hours both sides
04:00 Thu08:00 ThuOff-hours both sides
05:00 Thu09:00 ThuACST working
06:00 Thu10:00 ThuACST working
07:00 Thu11:00 ThuACST working
08:00 Thu12:00 ThuACST working
09:00 Thu13:00 ThuBoth at work
10:00 Thu14:00 ThuBoth at work
11:00 Thu15:00 ThuBoth at work
12:00 Thu16:00 ThuBoth at work
13:00 Thu17:00 ThuIST working
14:00 Thu18:00 ThuIST working
15:00 Thu19:00 ThuIST working
16:00 Thu20:00 ThuIST working
17:00 Thu21:00 ThuOff-hours both sides
18:00 Thu22:00 ThuOff-hours both sides
19:00 Thu23:00 ThuOff-hours both sides
20:00 Thu00:00 FriOff-hours both sides
21:00 Thu01:00 FriOff-hours both sides
22:00 Thu02:00 FriOff-hours both sides
23:00 Thu03:00 FriOff-hours both sides

Times computed for today in each zone using the IANA time zone database. The conversion accounts for daylight saving time wherever applicable.

About these time zones

India Standard Time (IST)
IANA identifier
Asia/Kolkata
Current UTC offset
UTC+05:30
Current abbreviation
GMT+5:30
Major cities in this zone
MumbaiNew DelhiBangaloreChennaiKolkata
Australian Central Standard Time (ACST)
IANA identifier
Australia/Adelaide
Current UTC offset
UTC+09:30
Current abbreviation
GMT+9:30
Major cities in this zone
Adelaide

Sun today in Mumbai and Adelaide

Mumbai
Sunrise
06:05
Sunset
19:06
Solar noon
12:36
Daylight
13h 0m
Adelaide
Sunrise
07:02
Sunset
17:23
Solar noon
12:13
Daylight
10h 20m

Related converters

ACST to IST (reverse)IST to ESTIST to PSTIST to GMTIST to UTCIST to CETEST to ACSTPST to ACSTGMT to ACSTUTC to ACSTCET to ACST
Looking for local time? See time in Mumbai or time in Adelaide.

Frequently asked questions

What is the time difference between IST and ACST right now?+
ACST (Australian Central Standard Time) is currently 4 hours ahead IST (India Standard Time). The exact difference can change when one or both zones transition into or out of daylight saving time.
Does IST or ACST observe daylight saving time?+
IST: does not observe daylight saving time. ACST: observes daylight saving time.
When is the best time to schedule a meeting between IST and ACST?+
The strongest overlap is 09:00–12:00 IST (13:00–16:00 ACST), giving 4 hours when both sides are within standard 9am-5pm working hours.
What time is it in Adelaide when it is 12:00 noon in Mumbai?+
When it is 12:00 Thu in Mumbai (IST), it is 16:00 Thu in Adelaide (ACST).
Which IANA time zone identifiers are used for IST and ACST?+
IST maps to "Asia/Kolkata" in the IANA database. ACST maps to "Australia/Adelaide". These identifiers are what most software libraries use to convert times accurately, including DST handling.
Is Mumbai ahead of or behind Adelaide?+
Whether Mumbai (IST) is ahead of or behind Adelaide (ACST) depends on the current UTC offsets. Right now ACST is 4 hours ahead IST. The live converter and side-by-side clocks above always reflect the current direction.
What are the current UTC offsets for IST and ACST?+
IST is UTC+05:30 (GMT+5:30) and ACST is UTC+09:30 (GMT+9:30). Both offsets shift by one hour when the corresponding region enters or exits daylight saving time, so the live values on this page are the source of truth.
Can I schedule meetings during business hours for both IST and ACST?+
Yes. There are 4 hours of overlap during standard 9am-5pm working hours, with the strongest window at 09:00–12:00 IST.