IST to CST converter
India Standard Time to Central Time. CST is 11 h 30 min behind of IST in January and 10 h 30 min behind in July.
From
IST · Kolkata GMT+5:30 · UTC+5:30
- CST · ChicagoCDT · UTC−5 · 10 h 30 min behind22:30Sun, Sep 27 · previous day
The gap between IST and CST
| 2026 | IST clocks | CST clocks | Difference |
|---|---|---|---|
| January | GMT+5:30 UTC+5:30 | CST UTC−6 | 11 h 30 min behind |
| July | GMT+5:30 UTC+5:30 | CDT UTC−5 | 10 h 30 min behind |
The gap changes on: Sun, March 8, 2026 (10 h 30 min behind); Sun, November 1, 2026 (11 h 30 min behind); Sun, March 14, 2027 (10 h 30 min behind); Sun, November 7, 2027 (11 h 30 min behind).
Convert the other way: CST to IST · Plan a meeting across more places
IST to CST time table
Every hour of the IST day and the matching CST time, for a mid-January and a mid-July date.
| IST | CST · January | CST · July |
|---|---|---|
| 12:00 AM | 12:30 PM (−1 day) | 1:30 PM (−1 day) |
| 1:00 AM | 1:30 PM (−1 day) | 2:30 PM (−1 day) |
| 2:00 AM | 2:30 PM (−1 day) | 3:30 PM (−1 day) |
| 3:00 AM | 3:30 PM (−1 day) | 4:30 PM (−1 day) |
| 4:00 AM | 4:30 PM (−1 day) | 5:30 PM (−1 day) |
| 5:00 AM | 5:30 PM (−1 day) | 6:30 PM (−1 day) |
| 6:00 AM | 6:30 PM (−1 day) | 7:30 PM (−1 day) |
| 7:00 AM | 7:30 PM (−1 day) | 8:30 PM (−1 day) |
| 8:00 AM | 8:30 PM (−1 day) | 9:30 PM (−1 day) |
| 9:00 AM | 9:30 PM (−1 day) | 10:30 PM (−1 day) |
| 10:00 AM | 10:30 PM (−1 day) | 11:30 PM (−1 day) |
| 11:00 AM | 11:30 PM (−1 day) | 12:30 AM |
| 12:00 PM | 12:30 AM | 1:30 AM |
| 1:00 PM | 1:30 AM | 2:30 AM |
| 2:00 PM | 2:30 AM | 3:30 AM |
| 3:00 PM | 3:30 AM | 4:30 AM |
| 4:00 PM | 4:30 AM | 5:30 AM |
| 5:00 PM | 5:30 AM | 6:30 AM |
| 6:00 PM | 6:30 AM | 7:30 AM |
| 7:00 PM | 7:30 AM | 8:30 AM |
| 8:00 PM | 8:30 AM | 9:30 AM |
| 9:00 PM | 9:30 AM | 10:30 AM |
| 10:00 PM | 10:30 AM | 11:30 AM |
| 11:00 PM | 11:30 AM | 12:30 PM |
About these two clocks
IST — India Standard Time. Used in all of India — Mumbai, Delhi, Bengaluru. India does not use daylight saving time, so IST is UTC+5:30 all year.
CST — Central Time. Used in Chicago, Dallas, Houston, Mexico City is separate. CST is the winter name; in summer the same clocks run on CDT (UTC−5). Conversions here follow the clocks.
All figures on this page come from the IANA time zone database (the same data your phone and laptop use), evaluated for the date in question. Abbreviations are ambiguous — “IST” also means Irish or Israel Standard Time, and “CST” is China Standard Time in Asia — so this page uses Asia/Kolkata and America/Chicago explicitly.
Questions people ask
How many hours ahead or behind is CST compared with IST?
CST is 11 h 30 min behind of IST in January and 10 h 30 min behind in July. The gap moves because daylight saving time starts and ends on different dates (or not at all) in the two places.
What is 9 am IST in CST?
On a January date, 9:00 am IST is 9:30 PM (−1 day) CST. In July it is 10:30 PM (−1 day). Use the converter above for any other date.
Which cities use IST?
India Standard Time (IST) is used in all of India — Mumbai, Delhi, Bengaluru. India does not use daylight saving time, so IST is UTC+5:30 all year.
Which cities use CST?
Central Time (CST) is used in Chicago, Dallas, Houston, Mexico City is separate. CST is the winter name; in summer the same clocks run on CDT (UTC−5). Conversions here follow the clocks.
When is a good time for a IST–CST call?
Look for the hours where both columns in the table fall between about 8 am and 6 pm. If none exist, the meeting planner on our home page shows the least-bad options and lets you share a link that converts for every attendee.
Related conversions
IST to ESTEST to CSTPST to CSTUTC to CSTIST to UTCIST to PSTIST to GMTIST to CETIST to AESTIST to JST