ADT to IST Time Converter

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

Halifax · Atlantic Daylight Time
23:01:48
Tuesday, May 12, 2026
ADT · UTC-03:00
Mumbai · India Standard Time
07:31:48
Wednesday, May 13, 2026
GMT+5:30 · UTC+05:30

Convert a specific time

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

Daylight Saving status right now

ADT (Atlantic Daylight 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: ADT observes DST while IST does not. The 8.5-hour difference shown above will shift by one hour when ADT starts or ends DST.

When can ADT and IST meet?

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01
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ADT
IST
Both zones in working hours (9am-5pm)
One zone working
Off-hours
Columns are hours of the day in Halifax (ADT). 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 ADT (16:30–18:30 IST).

Hour-by-hour ADT to IST conversion table

ADT time (Halifax)IST time (Mumbai)Status
00:00 Tue08:30 TueOff-hours both sides
01:00 Tue09:30 TueIST working
02:00 Tue10:30 TueIST working
03:00 Tue11:30 TueIST working
04:00 Tue12:30 TueIST working
05:00 Tue13:30 TueIST working
06:00 Tue14:30 TueIST working
07:00 Tue15:30 TueIST working
08:00 Tue16:30 TueIST working
09:00 Tue17:30 TueADT working
10:00 Tue18:30 TueADT working
11:00 Tue19:30 TueADT working
12:00 Tue20:30 TueADT working
13:00 Tue21:30 TueADT working
14:00 Tue22:30 TueADT working
15:00 Tue23:30 TueADT working
16:00 Tue00:30 WedADT working
17:00 Tue01:30 WedOff-hours both sides
18:00 Tue02:30 WedOff-hours both sides
19:00 Tue03:30 WedOff-hours both sides
20:00 Tue04:30 WedOff-hours both sides
21:00 Tue05:30 WedOff-hours both sides
22:00 Tue06:30 WedOff-hours both sides
23:00 Tue07:30 WedOff-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 Daylight Time (ADT)
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
19:06
Solar noon
12:36
Daylight
13h 0m

Related converters

IST to ADT (reverse)ADT to ESTADT to PSTADT to GMTADT to UTCADT 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 ADT and IST right now?+
IST (India Standard Time) is currently 8h 30m ahead ADT (Atlantic Daylight Time). The exact difference can change when one or both zones transition into or out of daylight saving time.
Does ADT or IST observe daylight saving time?+
ADT: observes daylight saving time. IST: does not observe daylight saving time.
When is the best time to schedule a meeting between ADT and IST?+
Standard 9-5 hours do not overlap. Extending to 8am-7pm gives a window of 08:00–10:00 ADT (16:30–18:30 IST).
What time is it in Mumbai when it is 12:00 noon in Halifax?+
When it is 12:00 Tue in Halifax (ADT), it is 20:30 Tue in Mumbai (IST).
Which IANA time zone identifiers are used for ADT and IST?+
ADT 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 (ADT) is ahead of or behind Mumbai (IST) depends on the current UTC offsets. Right now IST is 8h 30m ahead ADT. The live converter and side-by-side clocks above always reflect the current direction.
What are the current UTC offsets for ADT and IST?+
ADT 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 ADT and IST?+
Not during a strict 9am-5pm window. If both sides flex to 8am-7pm, the available meeting window between ADT and IST is 08:00–10:00 ADT.