IST to MST Time Converter

Mountain Standard Time (MST) is currently 12 hours 30 minutes behind India Standard Time (IST). IST is UTC+5:30 and MST is UTC-7. The table below converts every hour of the day between the two, and the call planner shows where working hours line up.

India Standard Time (IST)
--:--:--
(UTC+5:30)
Mountain Standard Time (MST)
--:--:--
(UTC-7)

Best Time for a Call

There is no overlap between 9:00 AM and 5:00 PM office hours in these two zones. Stretching to early mornings and evenings, the workable window runs from 7:30 PM to 9:00 PM in IST, which is 7:00 AM to 8:30 AM in MST. One side ends up outside normal hours, so alternating who takes the awkward slot is a fair way to handle recurring calls.

Comparing more than two places? The Overlap Zones tool shows working hours for several cities on one grid.

Hour by Hour: IST to MST

ISTMST
12:00 AM11:30 AM-1 day
1:00 AM12:30 PM-1 day
2:00 AM1:30 PM-1 day
3:00 AM2:30 PM-1 day
4:00 AM3:30 PM-1 day
5:00 AM4:30 PM-1 day
6:00 AM5:30 PM-1 day
7:00 AM6:30 PM-1 day
8:00 AM7:30 PM-1 day
9:00 AM8:30 PM-1 day
10:00 AM9:30 PM-1 day
11:00 AM10:30 PM-1 day
12:00 PM11:30 PM-1 day
1:00 PM12:30 AM
2:00 PM1:30 AM
3:00 PM2:30 AM
4:00 PM3:30 AM
5:00 PM4:30 AM
6:00 PM5:30 AM
7:00 PM6:30 AM
8:00 PM7:30 AM
9:00 PM8:30 AM
10:00 PM9:30 AM
11:00 PM10:30 AM

Rows marked office hours fall between 9:00 AM and 5:00 PM in both places. For a specific date, use the interactive converter.

Does the Difference Change During the Year?

IST and MST are fixed offsets, so the difference between them never changes.

This page covers India Standard Time, UTC+5:30, which has no daylight saving. IST can also refer to Irish Standard Time (UTC+1) or Israel Standard Time (UTC+2).

MST is UTC-7. Most of the Mountain region switches to MDT (UTC-6) in summer, but Arizona stays on MST year round.

Frequently Asked Questions

How many hours behind is MST compared to IST?

MST is currently 12 hours 30 minutes behind IST. IST and MST are fixed offsets, so the difference between them never changes.

What time is 9:00 AM in IST in MST?

9:00 AM in IST is 8:30 PM in MST on the previous day.

What is the best time for a call between IST and MST?

There is no overlap between 9:00 AM and 5:00 PM office hours in these two zones. Stretching to early mornings and evenings, the workable window runs from 7:30 PM to 9:00 PM in IST, which is 7:00 AM to 8:30 AM in MST. One side ends up outside normal hours, so alternating who takes the awkward slot is a fair way to handle recurring calls.