Zone & HourIST to CST Time Converter
CST is 11 hours and 30 minutes behind of IST.
IST: India Standard Time, UTC+05:30.
CST: Central Standard Time (North America), UTC−06:00.
For a city that changes clocks, use the date-aware city converter.
Check the abbreviation before converting
IST can also mean Irish Standard Time (UTC+01:00) or Israel Standard Time (UTC+02:00). This page always uses India.
CST is ambiguous: China Standard Time is UTC+08:00; Cuba Standard Time is UTC−05:00. Choose a city if you mean either of these.
Convert a time
9:00 AM IST = 9:30 PM CST (previous day)
24-hour IST to CST conversion table
These are fixed-offset examples. They apply whenever the two abbreviations have the exact meanings stated above.
| IST · UTC+05:30 | CST · UTC−06:00 | Day |
|---|---|---|
| 12:00 AM | 12:30 PM | Previous day |
| 1:00 AM | 1:30 PM | Previous day |
| 2:00 AM | 2:30 PM | Previous day |
| 3:00 AM | 3:30 PM | Previous day |
| 4:00 AM | 4:30 PM | Previous day |
| 5:00 AM | 5:30 PM | Previous day |
| 6:00 AM | 6:30 PM | Previous day |
| 7:00 AM | 7:30 PM | Previous day |
| 8:00 AM | 8:30 PM | Previous day |
| 9:00 AM | 9:30 PM | Previous day |
| 10:00 AM | 10:30 PM | Previous day |
| 11:00 AM | 11:30 PM | Previous day |
| 12:00 PM | 12:30 AM | Same day |
| 1:00 PM | 1:30 AM | Same day |
| 2:00 PM | 2:30 AM | Same day |
| 3:00 PM | 3:30 AM | Same day |
| 4:00 PM | 4:30 AM | Same day |
| 5:00 PM | 5:30 AM | Same day |
| 6:00 PM | 6:30 AM | Same day |
| 7:00 PM | 7:30 AM | Same day |
| 8:00 PM | 8:30 AM | Same day |
| 9:00 PM | 9:30 AM | Same day |
| 10:00 PM | 10:30 AM | Same day |
| 11:00 PM | 11:30 AM | Same day |
What IST and CST mean
IST: India Standard Time
IST here means India Standard Time, UTC+05:30. India does not currently change clocks seasonally. A representative location is Kolkata / Mumbai, whose IANA identifier is Asia/Kolkata.
CST: Central Standard Time (North America)
This converter interprets CST as UTC−06:00. Chicago changes to CDT (UTC−05:00) during daylight saving. A representative location is Chicago in winter, whose IANA identifier is America/Chicago.
Common conversion examples
- 6:00 AM IST becomes 6:30 PM CST on the previous day.
- 9:00 AM IST becomes 9:30 PM CST on the previous day.
- 12:00 PM IST becomes 12:30 AM CST.
- 6:00 PM IST becomes 6:30 AM CST.
- 9:00 PM IST becomes 9:30 AM CST.
Frequently asked questions
Does this table change for daylight saving?
No. The offsets attached to these abbreviations stay fixed. A city may switch to a differently named abbreviation. IST is not a daylight-saving designation in the interpretation used here.
Should I put an abbreviation in a meeting invitation?
Use an IANA city time zone and a full date. Abbreviations are useful shorthand when everyone agrees on the meaning, but they do not carry the complete rules that a calendar needs for recurring events.
Why can the day change?
The difference is 690 minutes. Adding or subtracting that amount can move the destination time before midnight or beyond the end of the source day. The last column makes that change explicit.