IST to CST Time Converter

Central Standard Time (CST) is currently 11 hours 30 minutes behind India Standard Time (IST). IST is UTC+5:30 and CST is UTC-6. 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)
Central Standard Time (CST)
--:--:--
(UTC-6)

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 6:30 PM to 9:00 PM in IST, which is 7:00 AM to 9:30 AM in CST. 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 CST

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

This page covers North American Central Standard Time, UTC-6. The region switches to CDT (UTC-5) in summer. CST can also refer to China Standard Time, which is UTC+8.

Frequently Asked Questions

How many hours behind is CST compared to IST?

CST is currently 11 hours 30 minutes behind IST. IST and CST are fixed offsets, so the difference between them never changes.

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

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

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

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 6:30 PM to 9:00 PM in IST, which is 7:00 AM to 9:30 AM in CST. One side ends up outside normal hours, so alternating who takes the awkward slot is a fair way to handle recurring calls.