IRST to IST Time Converter

Convert Irish Standard Time (IRST) to India Standard Time (IST). Both time zones are shown live below; current offset between them is 4h 30m ahead.

Dublin · Irish Standard Time
20:13:51
Tuesday, May 12, 2026
GMT+1 · UTC+01:00
Mumbai · India Standard Time
00:43:51
Wednesday, May 13, 2026
GMT+5:30 · UTC+05:30

Convert a specific time

From: IRST (Dublin)
To: IST (Mumbai)
--:--

Daylight Saving status right now

IRST (Irish Standard Time)
Observes DST
Yes
In DST right now
Yes
Next fall back
2026-10-25
Offset shift
UTC+01:00 → UTC+00:00
IST (India Standard Time)
Observes DST
No

Heads up: IRST observes DST while IST does not. The 4.5-hour difference shown above will shift by one hour when IRST starts or ends DST.

When can IRST and IST meet?

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01
02
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IRST
IST
Both zones in working hours (9am-5pm)
One zone working
Off-hours
Columns are hours of the day in Dublin (IRST). 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 IRST (13:30–16:30 IST).

Hour-by-hour IRST to IST conversion table

IRST time (Dublin)IST time (Mumbai)Status
00:00 Tue04:30 TueOff-hours both sides
01:00 Tue05:30 TueOff-hours both sides
02:00 Tue06:30 TueOff-hours both sides
03:00 Tue07:30 TueOff-hours both sides
04:00 Tue08:30 TueOff-hours both sides
05:00 Tue09:30 TueIST working
06:00 Tue10:30 TueIST working
07:00 Tue11:30 TueIST working
08:00 Tue12:30 TueIST working
09:00 Tue13:30 TueBoth at work
10:00 Tue14:30 TueBoth at work
11:00 Tue15:30 TueBoth at work
12:00 Tue16:30 TueBoth at work
13:00 Tue17:30 TueIRST working
14:00 Tue18:30 TueIRST working
15:00 Tue19:30 TueIRST working
16:00 Tue20:30 TueIRST working
17:00 Tue21:30 TueOff-hours both sides
18:00 Tue22:30 TueOff-hours both sides
19:00 Tue23:30 TueOff-hours both sides
20:00 Tue00:30 WedOff-hours both sides
21:00 Tue01:30 WedOff-hours both sides
22:00 Tue02:30 WedOff-hours both sides
23:00 Tue03:30 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

Irish Standard Time (IRST)
IANA identifier
Europe/Dublin
Current UTC offset
UTC+01:00
Current abbreviation
GMT+1
Major cities in this zone
Dublin
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 Dublin and Mumbai

Mumbai
Sunrise
06:06
Sunset
19:06
Solar noon
12:36
Daylight
13h 0m

Related converters

IST to IRST (reverse)IRST to ESTIRST to PSTIRST to GMTIRST to UTCIRST to CETEST to ISTPST to ISTGMT to ISTUTC to ISTCET to IST
Looking for local time? See time in Dublin or time in Mumbai.

Frequently asked questions

What is the time difference between IRST and IST right now?+
IST (India Standard Time) is currently 4h 30m ahead IRST (Irish Standard Time). The exact difference can change when one or both zones transition into or out of daylight saving time.
Does IRST or IST observe daylight saving time?+
IRST: observes daylight saving time. IST: does not observe daylight saving time.
When is the best time to schedule a meeting between IRST and IST?+
The strongest overlap is 09:00–12:00 IRST (13:30–16:30 IST), giving 4 hours when both sides are within standard 9am-5pm working hours.
What time is it in Mumbai when it is 12:00 noon in Dublin?+
When it is 12:00 Tue in Dublin (IRST), it is 16:30 Tue in Mumbai (IST).
Which IANA time zone identifiers are used for IRST and IST?+
IRST maps to "Europe/Dublin" 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 Dublin ahead of or behind Mumbai?+
Whether Dublin (IRST) is ahead of or behind Mumbai (IST) depends on the current UTC offsets. Right now IST is 4h 30m ahead IRST. The live converter and side-by-side clocks above always reflect the current direction.
What are the current UTC offsets for IRST and IST?+
IRST is UTC+01:00 (GMT+1) 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 IRST and IST?+
Yes. There are 4 hours of overlap during standard 9am-5pm working hours, with the strongest window at 09:00–12:00 IRST.