AST to IST Time Converter

Convert Atlantic Standard Time (AST) to India Standard Time (IST). Both time zones are shown live below; current offset between them is 8h 30m ahead.

Halifax · Atlantic Standard Time
01:02:39
Monday, May 11, 2026
ADT · UTC-03:00
Mumbai · India Standard Time
09:32:39
Monday, May 11, 2026
GMT+5:30 · UTC+05:30

Convert a specific time

From: AST (Halifax)
To: IST (Mumbai)
--:--

Daylight Saving status right now

AST (Atlantic Standard Time)
Observes DST
Yes
In DST right now
Yes
Next fall back
2026-11-01
Offset shift
UTC-03:00 → UTC-04:00
IST (India Standard Time)
Observes DST
No

Heads up: AST observes DST while IST does not. The 8.5-hour difference shown above will shift by one hour when AST starts or ends DST.

When can AST and IST meet?

00
01
02
03
04
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08
09
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AST
IST
Both zones in working hours (9am-5pm)
One zone working
Off-hours
Columns are hours of the day in Halifax (AST). Each row shows the local working-hours state in that zone for the same moment in time.
No overlap during strict 9-5 working hours; some flexibility needed.
If both sides are willing to extend to 8am-7pm, the available window is 08:00–10:00 AST (16:30–18:30 IST).

Hour-by-hour AST to IST conversion table

AST time (Halifax)IST time (Mumbai)Status
00:00 Mon08:30 MonOff-hours both sides
01:00 Mon09:30 MonIST working
02:00 Mon10:30 MonIST working
03:00 Mon11:30 MonIST working
04:00 Mon12:30 MonIST working
05:00 Mon13:30 MonIST working
06:00 Mon14:30 MonIST working
07:00 Mon15:30 MonIST working
08:00 Mon16:30 MonIST working
09:00 Mon17:30 MonAST working
10:00 Mon18:30 MonAST working
11:00 Mon19:30 MonAST working
12:00 Mon20:30 MonAST working
13:00 Mon21:30 MonAST working
14:00 Mon22:30 MonAST working
15:00 Mon23:30 MonAST working
16:00 Mon00:30 TueAST working
17:00 Mon01:30 TueOff-hours both sides
18:00 Mon02:30 TueOff-hours both sides
19:00 Mon03:30 TueOff-hours both sides
20:00 Mon04:30 TueOff-hours both sides
21:00 Mon05:30 TueOff-hours both sides
22:00 Mon06:30 TueOff-hours both sides
23:00 Mon07:30 TueOff-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

Atlantic Standard Time (AST)
IANA identifier
America/Halifax
Current UTC offset
UTC-03:00
Current abbreviation
ADT
Major cities in this zone
Halifax
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

Sun today in Halifax and Mumbai

Mumbai
Sunrise
06:06
Sunset
19:05
Solar noon
12:36
Daylight
12h 58m

Related converters

IST to AST (reverse)AST to ESTAST to PSTAST to GMTAST to UTCAST to CETEST to ISTPST to ISTGMT to ISTUTC to ISTCET to IST
Looking for local time? See time in Halifax or time in Mumbai.

Frequently asked questions

What is the time difference between AST and IST right now?+
IST (India Standard Time) is currently 8h 30m ahead AST (Atlantic Standard Time). The exact difference can change when one or both zones transition into or out of daylight saving time.
Does AST or IST observe daylight saving time?+
AST: observes daylight saving time. IST: does not observe daylight saving time.
When is the best time to schedule a meeting between AST and IST?+
Standard 9-5 hours do not overlap. Extending to 8am-7pm gives a window of 08:00–10:00 AST (16:30–18:30 IST).
What time is it in Mumbai when it is 12:00 noon in Halifax?+
When it is 12:00 Mon in Halifax (AST), it is 20:30 Mon in Mumbai (IST).
Which IANA time zone identifiers are used for AST and IST?+
AST maps to "America/Halifax" in the IANA database. IST maps to "Asia/Kolkata". These identifiers are what most software libraries use to convert times accurately, including DST handling.
Is Halifax ahead of or behind Mumbai?+
Whether Halifax (AST) is ahead of or behind Mumbai (IST) depends on the current UTC offsets. Right now IST is 8h 30m ahead AST. The live converter and side-by-side clocks above always reflect the current direction.
What are the current UTC offsets for AST and IST?+
AST is UTC-03:00 (ADT) and IST is UTC+05:30 (GMT+5:30). 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 AST and IST?+
Not during a strict 9am-5pm window. If both sides flex to 8am-7pm, the available meeting window between AST and IST is 08:00–10:00 AST.